Here is where you went wrong with the snake plants. They use a form of photosynthesis called CAM (crassulacean acid metabolism) photosynthesis. This is an adaption for mostly desert plants. They only breath at night so they do not produce oxygen when there is light on them. This is to help prevent water loss as it is cooler at night in deserts and the evaporation of water while breathing is less. They use CO2 and water at night to make a 4 carbon chained molecule which they will use during the day along with light to make sugar. So putting the plants in a room with the lights on did literally nothing.
@@miriamrobarts There are three main types of photosynthesis. C3, C4, and CAM. Only CAM give off oxygen at night and uses none during the day. The other two give off a lot of oxygen during the day and absorb a little of it at night. C3 and C4 plants are good for living spaces but not for bedrooms as they would reduce room oxygen at night. CAM plants, like cactus, snake plant and most succulents are good for bedrooms as they will increase room oxygen while you sleep.
@@GoalOrientedLifting Cactus, snake plants and most succulents and the pineapple plant are CAM photosynthesizes. Most desert palm trees use CAM as well. Areca Palms are interesting as they will use both C4 and CAM photosynthesis, producing oxygen day and night. But only if they are well watered. If under water stress, they will switch to CAM only.
I was part of a team that did a 90 day (mostly) closed loop life support system test at Johnson Space Center back in the mid 90’s. We used dwarf wheat plants. 22,000 of them. We planted 4 different crops in rotation. Harvesting and using this as part of their food. This gave us the average equivalent of about 1.5 persons worth of O2. We had a crew of 4 in the enclosure and they did at least 1 hour of vigorous exercise. I applaud your efforts to run this test just because you are curious 👏👏👏
Awesome dedication! I did a quick google search based on a hunch that was confirmed; snake plants are CAM plants, meaning they absorb CO2 and release O2 AT NIGHT and during the day photosynthesise using the CO2 they stored, also keeping the O2 inside. So in your setup their pores were not open to gas exchange. (FYI the reason they do this is because they are native to hot climates and opening their pores for gas exchanges makes them dry up in the hot days)
That is a very good point which I had totally forgotten. Come bedtime, your clothes spontaneously combust because of high oxygen levels. (Joke, unlikely to get that high.)
Very practical example from NASA 😂 You need continued photosynthesis for this to work, I think the algae also won't work after the medium tanks are saturated. You'd be safer in a tomato grow room with proper lights
I'm from Costa Rica, my great grandmother plant 2 trees of Cas in the yard of my house, cas is like small green guava, the trees already have more then 100 years they are huge and my house is in the middle of a city close to big Factory, and the difference of breathing in the yard of my house or going outside were there is not trees just small plants and closer to the factory is absolutely abismal, thanks to that I learn to appreciate and understand how important are plants or how amazing are the trees that are especially big, I notice the huge difference for the first time when I start to make exercise when I went to run or walk around my city I feel tired sooner then when I make excercise in my yard, the difference is insane the quality of the air is so much better that I can literally double the time and exercises and the feeling is so much better. Your video blow my mind, amazing content congrats and the best wishes for your projects.
Env researcher here: What lights were you using? Its relatively dark; they dont look remotely sufficient for your application. Plants are only going to process co2 via photosynthesis. If you are providing either insufficient or minimal light, then you can expect to observe either zero or minimal effect, respectively. I'd be interested if you tried it again, but build a chamber outside, with windows for lots of indirect sunlight (it'll be cheaper than buying leds). I would water the snakeplants until it drained out the bottom of the planters, wait 1 hour, and then commence testing. Dont forget your controls. One with no humans. One with no plants. One with neither. Lastly, it may get hot in there. Make a gameplan, even simple ice packs and a bottle of water for yourself.
Also, the soil in the snake-plants may contain aerobic bacteria that may slurp up extra O2 produced. (Although I think it's clear that the snake-plants weren't making much of a dent)
I’d say don’t even use humans during the test, too many variables. Humans to get the co2 up and o2 down, and an airlock to get out before testing. Or maybe even just pumping co2 in there. That eliminates water vapor, heat, and varying o2 to co2 conversion. Later, he might even try to take into account that that insulation is not impermeable. I can’t find the values for anything but water vapor though so I don't know if it’s appreciably affecting it.
ex-professional algae farmer here: That scale up from the pale green "piss bottle" up all the deep green 2 liter bottles was actually quite impressive.
I grew clamydomonas reinharditi for hydrogen in school, just getting to 5 liters of healthy algae really isn't easy. We ran a Co2 line in I think. But our hydrogen yield was terrible.
Absolutely love this video! I'm a scientist who dabbles in algae quite a bit - mainly Chlorella and Spirulina. Some tips and suggestions: Keep in mind that by adding baking soda (HCO3) to the culture medium, you are providing the algae with an easy source of carbon that will compete with the CO2 being bubbled in from the air. This is why recipes like Zarrouk contain around 20g of HCO3 per litre - they are designed for speedy growth. A solution of baking soda will also leak carbon into the air in the form of CO2 until an equilibrium is reached. Also keep in mind that photosynthesise will elevate pH; their metabolic activity will slow or even stop until you bring the pH back towards neutrality. Chlorella vulgaris can produce 8 daughter cells from a single parent under optimal conditions, so the pH can rise crazy fast and jump from 7 to around 10 - 10.5 in a day or two. You might want to try starving your cultures of carbon before using them in your experiment and use dilute HCl to keep your pH between 6 - 8. Also in my experience the lag between illumination and photosythensis is around 20 - 30 minutes. Hope this helps - looking forward to part 2 :)
quite a few people already commented on the day/night cycle of plants, so that's one thing. Another thing that is affecting your setup is the lights. LED lights are efficient because they produce a narrow range of light. Most LED lights are made to make a pleasing light for us humans, but may be near useless for plant photosynthesis. You need to look into what spectrum of light the algae really likes and see that your LED lights are actually producing that spectrum.
Chlorophylls absorb most strongly in the red and blue regions, for the most common ones in green algae, 420-435nm and 640-660nm range. Accessory pigments gather energy at other wavelengths, mostly yellow and orange range. Green is mostly reflected, thus green plants. White LEDs do a great job with the blue, but not as well in the red ranges, and they put out a lot in the useless green range. White LEDs with red LED supplement might do better. But another huge factor is simple light intensity. We tend to overestimate light intensity from artificial sources thinking they are brighter than they really are. Sunlight is orders of magnitude brighter. Light is what provides the energy and is often the limiting factor. Someone else with a scientific background noted, the lights don't look nearly bright enough.
@@michaelclark4876 Yep, many factors not covered. Water temp, surface area, density of algae, on and on....A lot of people calling this and "experiment", lol. This is not even close to high school science, however maybe it will motivate someone to do an actual experiment.
Thanks ...learning. I thought that from a non-science standpoint. Because artificial light is not natural light. I don't think there are any solar panels inside brightly lit laboratories to recycle the energy. I know this is different than the CO2-O2 cycle, but since they both involve energy transfer.... I will state again all speculation, non-science based speculation.
Joel's homemade Amazon grow lights were specific enough for him to mention for the huge food grade 100gallon barrels. the specific light wavelengths @michaelclark4876 mentioned DO need to be checked against those grow lights' wavelengths. which intensity are you talking about Mr. Clark? lumens? candlepower? watts? temperature is a variable too. what water temps does that algae like to grow the fastest at? will Joel need to HEAT or COOL that water? lifecycle of the algae. what is it like? how long do they live? when in their lives is their CO2 to O2 exchange rate the highest? what i'm ALSO curious about is Joel's 'food' and mineral mixtures. is he sugaring the water to feed the algae or is it general 'fish guts' liquid plant food? or pure nitrate/nitrogen algae food? if the mineral and 'food' ratios aren't perfect in Joel's water... his algae won't grow/divide/die/eat the dead/divide further etc. at perfect rates. Joel didn't mention the FLOW RATE and Cubic feet/meters per minute of air he is moving THROUGH his algae reactors as well as the Cubic feet/meters of air INSIDE his 'sealed chamber'. plus... he didn't double triple and quadruple check the airtight nature of his chamber. every. time. he. started. a. test. if any amount of 'outside air' gets in or 'inside the chamber air' gets out... all his ratios and rates are invalid. concrete is porous! it absorbs water, releases it, it as well as allows gasses to penetrate. did he rough up that section of concrete flooring in his basement, seal it with a polymer coating, polish it, seal it, and polish it again? or did he even lay down a few layers of plastic drop cloths like housepainters use? it didn't look like it to me in this video... he shoved multiple 100G barrels across the bare concrete floor. this is a pretty fun and funny video... but Joel left out a crapton of stuff!
Interesting experiment, but note that a significant portion of the CO₂ might just be dissolving in the large volume of water, potentially around 1.45 g/L at room temperature. To verify, measure the dissolved CO₂ concentration in the water with a CO₂ test kit, direct sensor, or by calculating it from pH. Consider this in your analysis to accurately assess the algae’s impact.
Was going to reply with this dame comment-- either track the water pH and O2% in the room as well or repeat the experiment with only water and no algae in the tanks to measure the buffering/scrubbing capacity of the water alone. Either way I love the spirit of the experiment, keep being awesome Joel!
FINALLY a guy who doesn't quit before reaching the final result, I've seen far to many people end the video with "it is possible but im not doing it" so thank you for going through with it
I haven’t seen any videos that quit, but MY problem is when it’s NOT possible, because I ALWAYS get my hopes up, and I can’t STOP being hopeful, because despite being pessimistic, I just think that the thought of it being possible is too interesting and/or cool to give up on believing! Besides, even *I* can’t be negative *all* of the time.
I am an astrobiologist. And before I get into this video any further than the claim, 6 to 8 plants is an incredible understatement. An average plant produces 5 milliliters of oxygen per leaf per hour. They also produce more or less at certain times of day, stage of their life cycle, light exposures, and temperature. People breathe about 7.5 liters of oxygen a minute. So, if we're talking about average plants in a highly controlled environment, a minimum of 90,000 leaves would be required to provide for one person's average oxygen needs. Algeas are actually responsible for between 50 & 70% of earth's oxygen production (depending on study and types of algea). Even then, dead and decaying algae can greatly reduce the amount of oxygen produced by the healthy ones. And weather patterns affect photosynthesis, as does night. This is a very difficult problem to solve, even for people who's jobs are to solve these problems. There are so many variables that we know but still likely even more we don't fully understand. Edit: I just finished the video and I am thoroughly impressed with the experiment thus far and can't wait to see part 2! Algae for the win!
Are there calculations that factor in the amount of oxygen that the plants themselves use to actually process the sugars from photosynthesis? 90,000 leaves but what if they did not use any oxygen at all, would it be reduced to say 60k or even less? I think one of the thing that people don't realize is that trees and plants produce oxygen but also breathe it as well, just not at the same rate.
@amelliamendel2227 Phytoplankton are a very efficient oxygenator and form the basis for all the ocean food webs. When we speak about phytoplankton, this term includes both microscopic single-celled algae and cyanobacteria. Algae is a very interesting life form. It has been around for billions of years. Our earliest fossilized records for it date to the Precambrian era. Cyanobacteria formed around 3.5 billion years ago. More complex multicellular red algae began forming about 1.4 billion years ago. Freshwater green algae is the most likely ancestor for all forms of plant life we have on earth today.
@cchavezjr7 I am sure that there are specific calculations for respiratory oxygen use in plants, but they are not something I deal with. I will ask some colleagues. I know that there is a net production of oxygen and how that helped us to be here today. I study the history of life, looking at where it first formed, how it evolved, and how it might evolve in the future. This helps us understand more about the effects our planet has on us and us on all life. It helps us to determine if life exists elsewhere and if we send missions to nearby planets, moons or possibly asteroids and comets (if transpermia is a theory we want to delve into), where we would expect to see evidence of life. It's fun to think about ways life could have been different here and what life might look like elsewhere.
Nasa never claimed it would produce enough oxygen. It was a study on household air pollutants, snake plants are good at clearing some of the VOCs in a sealed environment. Also, water is really good at holding co2 in the water column. Were you checking the co2 concentration in the water?
This could be a major compounding factor, also could affect the PH of the growing solution, and PH adjustment could introduce chemicals that react with some of the CO2.
Water is just great at holding dissolved gasses in general. I'd run the experiment with distilled water, aerated, just to see how long it takes to reach the threshold sans plants.
Not to mention. It looked like the snake plants were just recently split. Freshly turned soil releases CO2. So that likely threw off the snake plant numbers as well.
very good point, but it's important to know that the dissolved CO2 is equivalent to the CO2 concentration in the atmosphere. they don't CAPTURE it, the CO2 just dissolves based on the pressure off the gas, it's Henry's law. meaning they would slow down how fast the CO2 raises, but it would keep raising forever. also it's something you can calculate, so no control needed.
Same I was getting such MythBusters vibes from this. From the janky setup, to the science content mixed in, and of course the if it's worth doing it's worth overdoing mantra of the experiment. This was peak UA-cam MythBusters style content and I can't wait for part 2
We all think it's really cool! Hope this video blows up it deserves it man. I'm a dropout nerd and your content is so fun to watch, real science done in such a fun, quirky way👍
Probably someone already pointed it out. But snake plants are the worse choice possible in this scenario because they are adapted to first store energy during the day and breathe at night. If you give them light the plants will close their stomata during day to preserve water. It's often in the list of plants that are good for air quality because they provide that function during the night instead of doing it during the day so they complement the rest of plants but they are not particularly efficient at doing so. Choose bigger plants and fastest growing ones if you want to see a noticeable difference.
Also, you can't just keep ordinary plants in light conditions all the time, after a few days they really start to suffer, going yellowish and weak. They need at least some night, like we do.
Napkin math: The body burns ~2000kcal, give or take 500g of carbon, every day. Spirulina can grow about 25% per day. So in order to compensate 500g of carbon, you'd need about 2kg of Spirulina at ideal growth condition, ignoring water weight of the cells. Concentration seems to be around 0.5g per liter of solution so maybe you'd need roughly 4 tons of algae solution per person I guess
That's sounds like a lot, but that would only be 2m×2m×1m tank. And that seems pretty reasonable to me. What would the maintenance of such tank be like? Does the algae need to be cleaned and how often?
The energy burned by the body isn't a great measure as not all of that energy is created through an aerobic process, we also don't consume 100% of the Oxygen we breathe in. It's better if we look directly at the volume of air inhaled and the amount of oxygen removed from the air during each breath. The body needs about 750-800kg of Oxygen per year, this accounts for how little Oxygen we actually consume as a percentage of the atmosphere during each breath, while keeping the air comfortable to breathe. You can get away with about 16 tonnes (8 adult) of sycamore trees, assuming they continue to grow at a constant rate, they will output ~800kg per year of 02. The other issue with this question is, does 1 person breathe out enough carbon dioxide to feed that same number of trees. Spoilers, we don't. A single human will generate about 0.7kg of C02 per day, or ~250kg per year, enough for ~6 trees which can go through a max of 40kg of c02 per year per tree. While there may be some foliage that is better at producing 02 and eating C02, you'll never get a perfect cycle where a person outputs enough c02 for all of the plants while the plants simultaneously generate enough 02 for the person. If there was perfect efficiency in that way, we'd effectively have a chemically powered perpetual motion device.
Coming from an aquarist standpoint the issue is that air pumps do not really do a good job of gas exchange. its all about surface agitation. if you made an aquarium (any box that holds water) with the largest surface area you could fit in that room, and had a Ton of surface agitation (e.g. a strong spray bar) then it would have worked way better. You needed to manually pump your CO2 into the containers because they didn't have an open source to the air, only what was making its way into the pump.
I'm thinking big, shallow tanks stacked on top of each other with fans circulating air from the rest of the room through the vertical gaps between them.
If proper air stone (wood is really good) is used with strong air pump this setup will be better than surface agitation, just area of bubles need to be larger than top level surface, with my saltwater tank this holds true and air stone is better than surface agitation. Do not spread misinformation.
sounds like a shower head high above a cut in half big bucket would be almost the best..getting droplets in air for max surface area and then great surface agitation
00:01 The number of plants needed to survive in a sealed room 02:13 Testing the effectiveness of plants in producing oxygen 06:21 Indoor air quality can be affected by high levels of carbon dioxide. 08:28 Even with 12 snake plants, CO2 saturation rate remained high. 12:29 Portable photo bioreactor using small bottles has potential for oxygen generation. 14:58 CO2 levels rose despite operating at reduced capacity. 18:59 Creating affordable algae lighting for tank 20:56 Testing efficiency of algae for breathing needs. 24:48 Exhaling into the algae tank reduced CO2 by over 90%. 26:44 Testing the impact of plant reactors on oxygen levels in a sealed room. Crafted by Merlin AI.
Problem is.. what are you gonna do witht the carbohydrates. You'd need to burn them that excess fat and sugars.. By exercising.. Generating more carbon dioxide to turn into air
So I'm a microbiologist working on microalgae and the reason for slowing down of o2 production is actually the increase in o2 will inhibit the rubisco to function optimally actively preventing co2 from being converted into energy.
@goku445 so the co2 will dissolve a little but realistically the rate of gas exchange is extremely low. So if you are gradually reducing the concentration, amount of co2 dissolved will decrease
Heh heh, reminds me of my college days. I took a intro the plant bio and do remember them saying rubisco is one of the most inefficient enzymes out there.
One part of the experiment you might not have considered is the moisture content of the soil the plants are in. They are going to be most efficient when they have ready access to water, and since snake plants are succulents, people often leave them dry for too long.
@@weaponizedemoticon1131 Yeah, that's true. Also, he should have used some of the grass species, or the paulownia trees. These species have a unique photosynthetic pathway dubbed "C4" (no, it's not explosion related). This pathway essentially makes the photosynthetic process twice as efficient at gathering CO2 from the air. Look at species like "Pauwlonia tomentosa" or "miscanthus gigantius". They can reach heights of 10-15 feet in a single year of growth!
@@realzakariax Real sunlight could help, but artificial lights are just as effective, provided they are intense enough and have the right wave lengths. Those coloured grow lights you see on amazon are mostly made like that because they are cheap, and not because adding blue and red seperately actually makes a difference. As long as it is a mostly balanced white light, it is just as effective as sunlight.
yeah this video was so refreshing! ive seen people literally just stop at the zz plant phase of this experiment and it's SO frustrating when they give up
The Russian research on algae refers specifically to exposed 'surface area'. The same amount of liquid/algae in kids pools instead of small bottles, would have massively increased the surface area. This may have made a significant difference.
"Surface area" is a proxy for gas exchange and light availability. The bubbler takes care of the first one. I think the main question here is whether the light sticks are sufficient. However, open-topped pools definitely would not have been a better option in such a small room.
I've seen a 100 acre lake go from basically clear to pea soup in a matter of days after a big summer thunderstorm (lightning strikes knock nitrogen out of the atmosphere which then fall with the rain in the form of nitrates which feed the algae), it's crazy how fast they can multiply
There's no more powerful force in the universe than exponential growth. I'm sure if you filled the oceans with freshwater it could become a giant algae pond in a short amount of time with the right conditions.
@@DjDolHaus86 that would have to be one hell of a lightning storm, i'd guess the major contributor of nitrates to the lake was just storm water runoff contaminated with fertilizer or waste.
@@DjDolHaus86Also during big storms if lighting strikes on the water hundreds of fish and millions of tiny lifeforms tend to die, that also hugely spikes the nitrogen levels of the whole lake and will throw off the balance giving algae the perfect breeding ground to completely take over.
When I was a kid I always wondered why scuba divers didn’t just have a bonsai tree in their scuba tanks. It was when I was older I realized they didn’t produce much oxygen, but the whole how many plants to offset a human has always intrigued me.
It's not the number of plants, but the weight, as part of the mass of the plant is the carbon, this portion of the mass has to be increasing by the mass of the carbon in the exhaled air... so we're looking at maybe around 10g of carbon per hour. Different plants in different conditions will have a different portion of the weight being made up by that carbon, most of the weight is probably water, so... until you can see the weight of the plant growing by 1 gram every minute, you're probably wasting your time. The reverse is also true... when you exercise and lose weight, this weight loss is breathed out as the carbon and water in similar proportions. So if you breathe in and out of a large bag, measure its weight gain, that would give you a closer number for what you would expect the plants to need to grow, as this includes the water part. Think of the condensation when breathing out onto a cold window... that much water has to end up in the plant as fast as you breath it out.
*We can calculate the absolute minimum required energy input from first principles:* Max efficiency of white LEDs approx. 50% Max efficiency of algal photosynthesis approx. 8% Human resting metabolic rate approx. 100 watts So you'll need *at least* 2500 watts worth of LEDs illuminating your algae to keep up with your exhaled CO2. I think the barrels probably weren't lit brightly enough and a lot of the CO2 absorption you observed was caused by the CO2 just dissolving in the large volume of water (like watered-down soda).
@@alen91071 Human bodies get energy from the chemical reaction between food and oxygen (oxidation). The amount of oxygen required to support our metabolic rate of about 100 watts (100 Joules per second) is directly proportional to the amount of food oxidized by our metabolism per unit of time. The reciprocal principle holds for photosynthesis: every gram of emitted oxygen comes with a proportionate quantity of carbon-based biomass.
@@alen91071let me explain for you simpleton. You know how combustion engines work right? gas is carbon food for engines and food is carbon food for humans and nether can burn without oxygen and the byproduct is carbon dioxide that is chemically bonded when oxygen reacts with carbon giving off energy. and then plants use sunlight to knock carbon off co2 leaving carbon in the form of sugars and starch.
@@lukekambic3536I agree with that oxygen required to suport metabolic rate is proportional to energy produced by body. Resting metabolic rate is measured as heat of a body. My problem is how did you convert 100 watt of heat to a 100 watt of luminescence. In your claim human gets all energy from oxygen ->algae ->light source. en.wikipedia.org/wiki/Resting_metabolic_rate , en.wikipedia.org/wiki/Weir_formula
@@alen91071 I was only aiming for a rough estimate of the *minimum* energy requirement. When a human is at rest all metabolic energy ends up as heat. Efficiency of photosynthesis is measured in terms of the amount of biomass an organism can produce using a given number of photons of light. In the case of this experiment, the quantity of biomass produced by the algae has to roughly equal to the quantity of biomass (food) that was metabolically oxidized by an animal/heterotroph to produce the CO2 that the algae absorbs. Hydrogen also plays a role in all this (carbohydrates/photosynthetic splitting of water), but the factors should mostly balance out since biomass from different organisms tends to have broadly similar C:H ratios.
You should try one of those pots that I think expose the roots (?). As most of oxygen comes from roots too apparently, or at least some of the pots I'm thinking of claim they give 50-100% more oxygen.
This is fantastic! About a decade ago, I wrote some scifi stuff where people had algae air scrubbers. They would also extract the algae from the tanks, and freeze dry it as a food source. The system was about 5 feet by 10 feet by ten feet in size per crewman. The extra size was for automated processing machinery, and i felt it was 'realistic'.
I think we're actually frighteningly close to your writing becoming a reality! Though, you wouldn't be able to use the extra algae grown as a food source without also inputting something back into the system. Human waste might work, but it depends whether the algae (and whatever other lifeforms are in the scubbers) can digest it completely.
Those in this thread, you might like Isaac Arthur, a "futurist." He has done dozens of videos on how we could colonise moons, asteroids, other worlds, create artificial worlds, harvest energy from stars while using them to move the entire system, etc., including Fermi Paradox answers.
Former algae grower here, 2 things I should mention. You should have done a control of pumping the air you exhaled into just room temperature water. Water does have a slight ability to dissolve CO2 turning it into carbonic acid slowly lowering the ph of the water. This is all a factor of the water temperature, starting ph and the airflow moving through the water column. It will get saturated at some point but it is surprising how big of a carbon sink plain water can be. The relative short amount of time you spend in that room would also give skewed or frustrated results. Also like plants, algae have a cycle where they scrub more CO2 (usually at night) vs produce oxygen (usually in sunlight). But that all depends on the algae strain and feeding conditions.
Ah yes. I thought I remembered that plants produce CO2 vs O2 depending on the light /time of day, and that for the plant I was looking for it was O2 at night. I was looking in the comments for it :D. Good to know I am not imagining things.
Plants need Carbon to grow, and use photosynthesis from light to separate and concentrate Carbon and Oxygen. The more CO2, the faster the growth, with the lights on. No CO2 needed during dark periods. During the dark periods seems to be when the plant puts out the most Oxygen. Next time he'll have to try just the opposite. Or do more research on the topic..?!🤔👍💯✌️
The research by the russians said, that it should be roughly 80 sqft of exposed algae. Your algae tanks aren't being used fully. I think you are going to need more movement inside the tank to expose more of the algae to CO2 rich air (more air pumped through it or other ways to expose more, stirrer, etc.)
that's why they decided to use simple electrolysis of water to produce oxygen. submarines and the space station have been doing this for 50 years. He could have spent 20 bucks and just vented the c02 from the floor and the hydrogen from the ceiling
I hate to break it to you but you need good old incandescent lightbulbs to get plants to do photo synthesis at peak efficiency leds or “grow lights” don’t work well or at all
One thing I noticed is the lack of baffles. The bubbles aren't making contact with as much algae as they otherwise could. With baffles in the liquid it would slow the bubbles down instead of going straight up and only really mixing the top layer at best with comparatively narrow cones of interaction between the bubbles and algae, which should allow for a longer duration of interaction.
Also a propeller based agitator motor powered to create more momentum for turbulence. But them we can get into temperature and pH sensing and control. There is a limit to this DIY testing. Baffles is a good cheap improvement
The bubbles are meant to dissolve into the water. For aquariums, there are special micro-bubble aerators that make bubbles so fine they never make it to the surface. (I use an air trap instead. Basically, an upside down cup holding a small amount of CO2; as it dissolves, the pocket of CO2 disappears.) For his setup, regular airstones will work just fine. It will have to cycle the room air multiple times, but that's OK. You'd want that to help push out O2 as well.
As a quick back of the envelope calculation, a human using 2000 calories coming from a diet of 50% carbohydrates, 25% fat, and 25% protein releases roughly 800g of carbon dioxide, which is equivalent to roughly a half kilogram of starch/cellulose/etc. The algae tanks are absorbing a lot of biomass!
I corrected your maths, "Based on a quick back-of-the-envelope calculation, a human consuming 2000 calories per day from a diet consisting of 50% carbohydrates, 25% fat, and 25% protein releases roughly 323.7 grams of carbon dioxide daily. This amount is equivalent to about a third of a kilogram of starch, cellulose, or similar substances. The algae tanks are absorbing a significant amount of biomass!" Phytoplankton would be much more efficient for this purpose
@@amelliamendel2227Are you sure about the 323.7 grams of carbon dioxide? I did a simpler calculation using 1 glucose + 6O2 needing 6CO2 + 6H2O Assuming 4 kcal/g for glucose and 2000 kcal per day, that's 500 grams of glucose per day, which require about 733.3 grams of CO2
Smarter way of calculating this is just trying to make a system that makes the equivalent calories you consume. That would be the true equilibrium. Plus you would get enough food to maintain yourself.
@@yusuftekten2652 You would need to always exert yourself exactly the same amount every day without any variation; better to just allow for a range by having some kind of buffers. Plus it would require a lot more investment, research and adaption to fully recycle your urine and feces back into food and clean water to make a full closed loop.
Snake plants only exchange gases at night due to their Crassulacean acid metabolism (CAM) so you need C3 or C4 plants to absorb co2 and release oxygen when lights are on. You could use Bamboo or Cannabis since those are very fast growing plants in the right conditions.
@@trealin4730 Sure, but that would have ruined the fun of the video. This is made for entertainment dude, and it would get the same end result either way, this way is just more entertaining to watch.
Right? I have snake plants in the back yard, and thought "oh, ill get some in nice pots and bring a few in." that quickly turned into "oh, well my house isnt big enough" to "well, a green lava lamp thing would be cool" to "oh, well I only have the blue 50 gal drums", then back to "oh, well my house isnt big enough..... whats for lunch?"
I used to be super into this exact kind of bioscience. The biggest problem is never not going to be the surface area of the algae and consequently the amount of light they get. Some of the most effective setups I've seen use either very long 2-3 inch acrylic tubes, or large acrylic windows sandwiched together, laid out like solar panel arrays.
The solution, then, is paneling the hallways inside/outside the station with thin (~1-2inch thick, tops) tanks. Add a thin air line for a micro-bubbler, and you have more than enough surface area on a spacecraft to make that oxygen. The only long-term problem becomes cleaning/recycling your algae.
Strings of LED directly imersed in an Algae vat with mirrored walls seems the best solution for an enclosed space. Trying to collect sunlight directly onto plants of any kind is a fools errand, a spacecraft would collect solar power from thin and high efficiency panels and then produce maximally photosynthetically efficient light resulting in minimal waste heat problems and minimizing pressurized volume.
Maybe a better medium for the light, immersed in the algae, could work? Like plunging a large amount of dense, clear, open cell foam into the algae. Could be made of acrylic. Maybe in combination with lining the barrels with a reflective surface? Something like that?
I don't think the problem is the plants. I knew it wouldn't work right away just looking at the lights in the first setup. In order to photosynthesize away 1 human worth of CO2 (about 1kg O2 per day), you need like 2500 watts of grow lights, minimum. Doesn't matter what kind of plant so much, cause there's no free lunch. Can't turn CO2 back to O2 without energy. Also, the plants, being alive, will use up O2 and output CO2 just like all living things. They can only do the photosynthesis with enough light. The real variable isn't the gallons of algae mix, it's the extra grow lights and pump/scrubbing. I suspect it can be done with fewer barrels, just more concentrated, if you put like 5 of those light sticks in each one.
@@DG-iw3yw Yes, more efficient LEDs that only produce the right wavelengths would lower the electricity requirements! However, filtering doesn't help, since that can only absorb energy.
As a former U.S. Navy Submarine sailor, There is a reason the submarines have chemical C02 scrubbers. Even though the submarine has oxygen generators, C02 will continue to build. I guess the Navy decided it was not feasible to have a few hundred gallons of algae per sailor on board. Oh, I have wondered about plants and oxygen generation since I was around 10..I saw a movie (comedy,1969) "Hello, Down There", made me want to build an undersea habitat....Maybe joining the Submarine Service wasn't so strange after all.
Well, I think there's the fact that on a sub that there are what, 100-150 people on board? Then there's every piece of machinery running, electronics breathing, food being cooked, all kinds of factors going on there... The other difference here is, on a sub, you get to come up for replenishment, in space, you might not get that... Algae will theoretically, grow as long as you're breathing to feed it... 👍
@@obsidianjane4413 there is a chemical compound that can smolder for a while, and it’s off. Gas is pure oxygen, that’s one of the things they used to generate more oxygen aboard a submarine. It was a whole video on the subject of oxygen generation, and CO2 scrubbing on UA-cam. You should go check it out.
The surface layer of the ocean is teeming with photosynthetic plankton. Though they're invisible to the naked eye, they produce more oxygen than the largest redwoods. Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean.
Awesome project, I love how the algae containers just keep scaling up. My guess is that you are going to need at least 100 times as much light as you've got. Light is what powers the conversion, so you could have a whole ocean of algae and it wouldn't make enough oxygen if you don't provide enough light.
hi, i really appreciate your work, i want you to help u in this project. here is the things you need to know. to survive 1 human we need 800 grams of oxygen per day (660 liters). so in order to get that much oxygen with the help of algae. we need 200 liters (50 gallon drum) of water, with 3 grams of biomass of algae per liter. which is equal to 600 grams of biomass. which produce about 960 grams of oxygen. in order to grow 3 grams of biomass per liters you need more aeration and more lighting. and another important aspect is nutrient concentration . the required concentrations are : 1. 30 mg of potassium nitrate or sodium nitrate per liter. 2. 3mg of phosphorus (Dipotassium Phosphate or Dipotassium Phosphate) per liter you need to add these nutrients every other day or every 2 to 3 days depending upon the growth i hope this data will help you in next video. if this data helped you, don't forget to reply. thank you.
When people joke about those algea tanks that were shown and proposed to be put in cities and said "why not ya know trees these are ugly" this is why, trees are amazing at cleaning up the air but people really forget how much ocean life is also doing it and its crazy efficient
The reason trees are nice in cities is not the oxygen production, it's the shade and evaporative cooling they provide, not to mention the psychological benefits.
It wouldn't be that horrid if instead of simple cylinders, they had aesthetically pleasing shapes. You'd basically get a translucent sculpture with green water and bubbles swirling it like some kind of retro-scifi movie set. At least it would be a nice decoration. Probably quite expensive to run though.
Points for trees: Trees in cities are eventually giving lumber when they're taken down and replaced with younger trees. Trees have little maintenance apart from the occasional branch removal / risk assessment. Trees also offer shade as mentioned by inv41id, serve as habitat for birds, keep the soil healthy and offer shelter for other critters. Points for algae: Schools can make science interesting and give this kind of project a massive boost in efficiency by putting it through many hands/iterations/climates. I'd love to see a basic setup for people to make, with sensors for the necessary chemicals/elements, an easy way to upscale a setup or sideways scaling (horizontal), semi-automatic resetting and maybe adding a mechanism that selectively composts the surplus algae (that no longer grow).
Hey brow, I worked with Chorella when graduating (Chemical Engineer). I'm not going to spoil the fun for you, but to give you a hint: * Search for the optimum light spectrum for your Chorella sp. (it's in nm of wave length) to absorb and actually produce O2. Also, be aware that Chorella grows WAY TOO FAST. Meaning: it multiplies its cells in numbers in a few days, then caps it, then start dying A LOT! Search for the cell number growth curve (ps: the green color you see is misleading). Congrats for your abservations, you've been doing such an Amazing Job =)
exactly what i was thinking as an engineer here: wave lenght of the light and how much "room" does the algae have to multiplicate since it needs to multiplicate to make oxygen. That being said: the guy is amazing.
@@fashiharz8584 No, man. Algae is the way to go if you want oxygen "from nature". Ideally, to artificially create/inject oxygen in a room you would use oxy-redox inorganic reaction, they are way more efficient and easier to control. The oxygen available on earth is available abundantly because of algae. Trees are actually useless. They consume what they produce except for a short period of time (photic compensation point). It's hard to make trees/plants/complex organisms to produce oxygen enough to make an environment breathable, way to many space, way to many variables. As a matter of fact, 99% of those so called "env scientists" know absolutely bollocks about biology. Trees have other roles in the ecosystem, oxygen wasn't, neither will never to produce oxygen for other living creatures.
I like how you just progressively revealed that each test was a fakeout, and that the "real" test was just starting, before revealing your ridiculous new setup you've been working on the whole time. You got really invested in this whole thing.
Here's the things I'd do to improve your setup: 1. Connect them in series rather than in parallel. Pump air from the room, or the mask, into the first tank, then the output of that tank into the second tank, and so on. This gives the air with higher CO2 more time with algae water, and thus more time to be cleaned. 2. Introduce a counter-flow by pumping the algae-water from the bottom of the last tank into the top of the second-last, and so on until the first, then pump from the bottom of the first tank into the last tank. This way, the algae processes its CO2 encountering higher and higher concentrations and then gets a rest; meanwhile, the CO2-saturated air goes through passes of fresher and fresher algae-water before being released back into the room. 3. Ideally you'd want small-diameter, tall bubble-columns with your lights and hoses in the center, thus ensuring maximal utilization of the available algae water by reducing the possible paths the bubbles can take, and thus algae-water that might not see many bubbles, and also having most of the algae-water near the lights, giving it the best ability to use the CO2 bubbles it encounters. 4. It would be possible to flow the algae-water over specialized 3d printed vanes to maximize the surface area of the water in contact with the air, and blow the air through the vanes rather than pumping it. This technique is used in Carbon Capture Storage with lime water rather than algae, to capture CO2 from the air.
@@TheNebulaEffectMinecraft easy just put a few drops of pee in them and pray you have a healthy microbial flora to break down the ammonia into nitrogen
That's what I was thinking the entire video. Skip the small tanks, and place 5 light setups in each of the large tanks. Also may need to reduce the amount of Chlorella in each tank. Not only do they block light from each other, but as waste products (including oxygen) build up in the water, it likely reduces the efficiency of CO2 scrubbing.
I'd also consider the plants were probably stressed during transport which can factor in on growth rate and also consumption rate. The plant's I'm familiar with use more co2 during the flower stage, so that's something else to consider. I'm no proctologist but I'd probably seek the advice of one before testing.
At so many different points in this video 99% of content creators would have just given up and called it a failure, so glad that this amount of hard work blew up for you.
Just a tip on your door. They make a sticky zipper for sheets of plastic. This might help with sealing the room. Another idea, PVC skeleton cube and just heat shrink the whole thing in plastic like your window. Rope Lights might not be a bad way either. Not sure if they provide the right type of light.
I'm an amateur game developer and writer and one of my game concepts was a bunker miles underground that had a "Green Level" to supply food and air. I wondered how much plants per person I'd need in the game to make it realistic. Thanks.
Plants only really absorb CO2 while growing, so calculate the growth mass of the plants multiply by about 0.8 and you get a very very rough number of how much CO2 is removed. You can find how much CO2 an average person produces per day, and do a fast calculation on how many plants you need. Just as a warning it's an extremely large number as you can not calculate the mas of the plants, only the mass of what is growing, which is a very small amount of the total mass for most of the life of the plant.
The air pump helps more then you probably realize. Water also sequesters co2 by desolving it into carbonic acid. Using the air pump increases the consentration inside the jugs, forcing the CO2 to be sequestered and desolve. If you checked the acidity of the water before and after, you'd see it's grown slightly more acidic.
Quite an interesting hypothesis with CO₂ dissolving, very much needs a test. Also it might also be good to put the light on the walls of the tank instead of the middle so more algea get it. On the fountain idea, "common sense"(quote because ye it can be quite unreliable) would say it's better for them to have both CO₂ and light at the same time, but I suppose the reaction not being that fast could make it not a problem.
Correction on one of your sentences. you 100% definitely die from missing o2. But our bodies are designed to react and realize it's dying only due to co2 oversaturration. In that way, if you had no o2, but NOT an abudance of co2, you can die without ever knowing you are. That's where horror stories like, a guy dies after kneeling down to tie his shoe, not realizing he knelt down near a sulfur pool pit, comes from.
This is awesome. I have been wondering about this for a long time and remember when I saw that movie I just felt it wouldn't work with so few plants and in such a large area. I was a kid also. Great work. It was also entertaining. Thank you
I'm fascinated by this! I did some research and maybe this would be helpful for your next experiment: 1. To meet the daily oxygen requirement of 550 liters (approximately 735 grams of oxygen), you would need around 24.3 gallons (92 liters) of Chlorella vulgaris culture. 2. Algae, like all living things, undergo a process called respiration, during which they break down organic compounds (produced during photosynthesis) to release energy. This process involves the consumption of oxygen and the release of carbon dioxide. Essentially, algae take in oxygen from the water and use it to oxidize organic molecules. As a byproduct of respiration, carbon dioxide is released back into the water. This is the opposite of photosynthesis, where carbon dioxide is taken in and oxygen is released. This process occurs during hours of darkness. 3. I'm not sure if your keeping your Chlorella Vulgaris under lit conditions 24/7 or not, but it may allow for more efficient photosynthesis during your next experiment to give them at least 8 hours of darkness before starting the experiment. I can't wait to see your next video!
Is that 24 gallons of culture or overall with water? I have an idea, but it depends.on whether it can be done in a 55gallon drum or needs a swimming pool.
@totallylegityoutubeperson4170 The culture volume includes water (the medium for algae) and necessary nutrients. 24.3 gallons would assume having achieved carrying capacity (the maximum population size of a species that an environment can support indefinitely).
Photosynthesis happens from 400-700nm and is not limited to blue and red. Why do you think high end led grow lights are white? They use a full spectrum.
@@johnjohnson8424 Er, no they are blue and red. Do a search for "horticultural lamps" and you will see that they intersperse blue and red LEDs of wavelengths tuned to the plants requirements. It is a waste of energy illuminating with green, because the plants reflect green. To our eyes these lamps appear purple, not white. Some lamps do also include white LEDs, (among the red and blue LEDs) but that is for growing flowers. I never saw a flower growing from algae. Curiously, on another channel there was discusssion of using green light to cause water to evaporate more quickly. Which is precisely what plants would not want.
Social media post was way out. Going to the primary literature: ...249 potted Dracaena lutescens would be required to completely remove all of the exhaled CO2 from a single occupant, in a completely unventilated room. This number is slightly reduced if high light adapted Howea forsteriana under 350 micromol PARm−2 s−1 (VERY bright lights) is considered; due to its greater leaf area, 206 individual plants would be required. These estimates are obviously impractical... From a paper on this very topic: Torpy FR, P.J. Irga, M.D. Burchett (2014) Profiling indoor plants for the amelioration of high CO2 concentrations. Urban Forestry and Urban Greening 13: 227-233. A large green wall (4-5 m2) with plenty of light would work on paper... Great video!
350umol is bright but not crazy light. It's about average for naughty lettuce. Sunlight can peak around 2000umol. I have an SQ520 quantum par meter and designed LEDs for nearly 2 decades.
@@N4CR Agree with that. We decided on 350 umol by walking around a university building with a light meter: we recoded it about a foot in front of a feature light. No reason why it couldn't be used for a green wall...apart from being a bit glary for occupants. We also use naughty lettuce light systems in the lab :)
People always talk about snake plants, but anyone who’s owned a snake plant knows they have low metabolic activity. They’re the turtles of the plant world. A faster growing plant with more photosynthetic activity would in theory work better I feel.
Doing a little Google-fu... a typical plant leaf produces around 5 mL of oxygen/hour. A typical human needs about 50 L of oxygen/hr. So that's 10,000 houseplant leaves, or somewhere between 500 and 1000 houseplants.
so does that mean that if we have less than green team than (population of earth*1000plants) , we slowly die? no one is measuring/monitoring this now globally 💀☠ fuuuuu
Yes i agree, you need something that grows quickly and aggressively (the same reason that algae was selected) The only reason i could see going with plants instead of algae that i could see is if you wanted dual purpose (food, emotional well being) and of course oxygen production. I also think that having powerful lights in the photosynthesis spectrum and as powerful as possible would help greatly. (Energy input)
@@cajunboy67 Another thing is, 1/2 the world is in darkness 1/2 the time (nominally). The Creator of this world is pure genius. Am I the only one to realise that?
Oh my! This setup is amazing. I really enjoyed the video, so many useful tips. I really appreciate your use of limited space in the layout. Ever since purchasing a portacapture x8 from Sweetwater, I am all in. Top notch all the way. Thank you for making it personal.
"I don't know if this video will do well, but *I* think it's cool" is the line I want to know is running through every UA-camr's mind when making a video.
You could add nets horizontal inside the barrels so that the bubbles get stuck to them and spend more time inside the water and get more exposure to the algae. That could also improve the effinency.
He was worried that no one would care about this video? It’s only been 20 hours (less than a day) and it already has almost 250 THOUSAND views. His second most popular video (of the ones that have only been around for a year) has 1.5 Million. If we assume that the views on this triple in a week (which is a very fair assumption) he could have half of those views in just a WEEK! He could have half of the views of one of his most popular videos in only 1/52 or 02% of the time! This video is definitely blowing up! Your work has payed off
@@ZaeOSWS most photosynthetic organisms tend to slow down after a certain point. You don't usually run grow lights 24\7 with many species, they need some time to "rest". Algae can take more hours than most plants, but some species still at least slow down their CO2 intake for a while.
@@aggonzalezdc The other problem is different types of algae work best with different types of light. Frankly the biggest problem I see in all this is the light sources he is using. There is a reason the professional light source was 2000 dollars a pop. It probably provided a much broader spectrum of light than his DIY version. Is also the reason that pot farmers use special grow lights when they farm inside. The light matters a lot more than he seems to realize.
Something for your consideration, as an avid fish keeper one of the first most important things you learn about keeping cichlids is that they have a high demand for dissolved oxygen. When you use a pump you are pumping in oxygen which dissolves partially into the water from surface agitation. Since you start with significantly more oxygen than co2 you are basically instantly reducing your oxygen to co2 ratio until you reach the point where atmospheric co2 is dissolving into the water as fast as the oxygen being pumped into the barrels is since your pump is on top of the barrel and co2 is a heavier molecule meaning it is resting closer to the floor. If I were you I would either work to create a convection current in the room, place the pumps on the floor, or get rid of the pumps entirely, and put under water circulation systems like wave makers designed to create surface agitation inside of the water since co2 dissolves 200x more freely than oxygen does forming carbonic acid. Additionally, adding baking soda increases the PH too severely. I would wait to add the baking soda until later in the test as all plant life grows more quickly in a lower PH/softer water environment, and I would even consider adding tannins to the water via wood or leaves to provide readily available nutrient supplies for the algae to take off with.
Biology student here. Fun fact: civilization would be fine as far as oxygen goes even if all green plants on Earth were destroyed (because the ocean produces a large percentage of our oxygen). The problem would be that the food chain would deteriorate so we wouldn't have meat (because carnivores and omnivores eat herbivores who eat plants)
I’m pretty sure even without the oxygen producing ocean life, humanity would have enough oxygen for billions of us to survive thousands of years. Even with the massive amount of fossil fuels we’ve used, creating 2,400 Gigatons of CO2, that only raised CO2 levels from .02% to .04%. Given that the O2 levels are more than 20%, and the average human needs about 1 ton of oxygen per year - all humans on earth use 8 Gigatons/year. The total amount of oxygen in the atmosphere is about 2.6 Petatons (10^15, or million billion tons), so thats at least 325,000 years of 8 billion humans. After half of that, it’ll start becoming harder generation after generation to get enough oxygen and people will live closer to sea levels and it’ll become harder to reproduce, reducing the population needed to support, and causing natural selection to support humans that need less oxygen (becoming shorter, decreasing metabolic speed, etc). but that’s enough time to figure out how to get more oxygen
Not a very good biology student. The O2 produced from the ocean comes from the plants in the ocean. If you _meant_ all the LAND based plants, then sure. As for the food chain, it'd make little difference to humans, as we could just farm the oceans exclusively.
maybe he could use some lights to just throw only the amount of wavelength of light that plants need. idk if i'm mistaken, but probably somewhere between the red colors
@@LeftSoulz its verry difficult to recreate sunlight inside. One reason is the combination of wavelengths, another is simply the immense power output needed. The sun provides every sq.meter with around 1300W of power. Most indoor led lights simply output around 5 to max 40W (old light bulbs) maby max.80W. That is a drastic contrast to the 1.3kW from the sun.
The next part should include growing hemp in the algae water as the hemp roots will use the extra nutrients in the water and the hemp leaves will grow very fast while providing extra oxygen and a product that can be fed to rabbits who will provide meat and manure which can fertilize all the plants. You really need a complete system for life on Mars.
So there's been a confusion here from the beginning. The post was about how many plants were needed to meet your oxygen needs, right? But you're measuring CO2 absorption. Those aren't the same thing, right? Maybe 6-8 snake plants are sufficient to supply your oxygen needs, if you have a CO2 scrubber.
About 10 minutes in and I started thinking theres no way that little light is enough to create the carbon chains required here. I would love to know how much water you needed in total, I imagine you needed a ton. Would be expensive to get into orbit, I imagine that is part of the reason why we are trying to find it in space like on the moon.
My childhood question wasn’t ever “how many plants do I need to breathe on mars” it was always if you could stick plants into a diving tank so people could breathe forever underwater
Rebreather diving is kinda like that though it just filters out co2 and not turn it back to o2. But you can carry like a few days of o2 in a tank when rebreather diving so it's fine.
The ocean supplies most oxygen for humans not plants, there is way more ocean than plants which mostly supply animals and insects especially those in forests which as we know are being chopped down for humans to grow vegetables and livestock hence animal extinction, Every drop of ocean water has millions of diatoms which create oxygen when diatoms die they become fertiliser for forests over millions of years check out, documentary ONE STRANGE ROCK
Thank you for revealing you already had that set! So often UA-camrs have some really elaborate set up for a one-off video and you wonder how the hell they financed and or justified it. Seeing how intricately decorated your set was, it makes so much more sense now. Thanks again.
Here is where you went wrong with the snake plants. They use a form of photosynthesis called CAM (crassulacean acid metabolism) photosynthesis. This is an adaption for mostly desert plants. They only breath at night so they do not produce oxygen when there is light on them. This is to help prevent water loss as it is cooler at night in deserts and the evaporation of water while breathing is less. They use CO2 and water at night to make a 4 carbon chained molecule which they will use during the day along with light to make sugar. So putting the plants in a room with the lights on did literally nothing.
Yes. I was going to say but you did.
Thanks, I was looking for a comment about this, since I thought I had heard something in the past about plants giving off oxygen at night.
Thank you, this answered a seperate question i had. btw do you know if other plants have a version of this for those extremely hot and dry days?
@@miriamrobarts There are three main types of photosynthesis. C3, C4, and CAM. Only CAM give off oxygen at night and uses none during the day. The other two give off a lot of oxygen during the day and absorb a little of it at night. C3 and C4 plants are good for living spaces but not for bedrooms as they would reduce room oxygen at night. CAM plants, like cactus, snake plant and most succulents are good for bedrooms as they will increase room oxygen while you sleep.
@@GoalOrientedLifting Cactus, snake plants and most succulents and the pineapple plant are CAM photosynthesizes. Most desert palm trees use CAM as well. Areca Palms are interesting as they will use both C4 and CAM photosynthesis, producing oxygen day and night. But only if they are well watered. If under water stress, they will switch to CAM only.
I was part of a team that did a 90 day (mostly) closed loop life support system test at Johnson Space Center back in the mid 90’s. We used dwarf wheat plants. 22,000 of them. We planted 4 different crops in rotation. Harvesting and using this as part of their food. This gave us the average equivalent of about 1.5 persons worth of O2. We had a crew of 4 in the enclosure and they did at least 1 hour of vigorous exercise. I applaud your efforts to run this test just because you are curious 👏👏👏
That’s totally awesome lol. Did you have any involvement with the bio sphere 2 project?
Cool stuff right here
22,000 plants for 1.5 people. Damn. I guess we could start sending seeds over to mars now and just wait 50 years lol.
i wonder what does space stations use for oxygen then?
@@anoobis777 The Russians created an electric powered oxygen creation machine
Awesome dedication! I did a quick google search based on a hunch that was confirmed; snake plants are CAM plants, meaning they absorb CO2 and release O2 AT NIGHT and during the day photosynthesise using the CO2 they stored, also keeping the O2 inside. So in your setup their pores were not open to gas exchange.
(FYI the reason they do this is because they are native to hot climates and opening their pores for gas exchanges makes them dry up in the hot days)
That is a very good point which I had totally forgotten. Come bedtime, your clothes spontaneously combust because of high oxygen levels. (Joke, unlikely to get that high.)
I came down here to find this comment. I was thinking this from the start.
Very practical example from NASA 😂
You need continued photosynthesis for this to work, I think the algae also won't work after the medium tanks are saturated.
You'd be safer in a tomato grow room with proper lights
id love to see the test with snake plants redone at night with this knowledge!
oh I didn't know about that. I still doubt they absorb enough CO2, but it's still interesting information.
I'm from Costa Rica, my great grandmother plant 2 trees of Cas in the yard of my house, cas is like small green guava, the trees already have more then 100 years they are huge and my house is in the middle of a city close to big Factory, and the difference of breathing in the yard of my house or going outside were there is not trees just small plants and closer to the factory is absolutely abismal, thanks to that I learn to appreciate and understand how important are plants or how amazing are the trees that are especially big, I notice the huge difference for the first time when I start to make exercise when I went to run or walk around my city I feel tired sooner then when I make excercise in my yard, the difference is insane the quality of the air is so much better that I can literally double the time and exercises and the feeling is so much better. Your video blow my mind, amazing content congrats and the best wishes for your projects.
That's awesome, take good care of those trees!
Heh heh. Breading. I read that as breeding which gave your story a very different flair.
@@fxbear lol i was 100% sure I write breathing, thanks
Env researcher here: What lights were you using? Its relatively dark; they dont look remotely sufficient for your application. Plants are only going to process co2 via photosynthesis. If you are providing either insufficient or minimal light, then you can expect to observe either zero or minimal effect, respectively.
I'd be interested if you tried it again, but build a chamber outside, with windows for lots of indirect sunlight (it'll be cheaper than buying leds).
I would water the snakeplants until it drained out the bottom of the planters, wait 1 hour, and then commence testing.
Dont forget your controls. One with no humans. One with no plants. One with neither.
Lastly, it may get hot in there. Make a gameplan, even simple ice packs and a bottle of water for yourself.
Also plants like this do not release oxygen during the day, they do it at night... During the day process and store it.
Also, the soil in the snake-plants may contain aerobic bacteria that may slurp up extra O2 produced. (Although I think it's clear that the snake-plants weren't making much of a dent)
@@a64738 Close, but it's the other way around.
I’d say don’t even use humans during the test, too many variables. Humans to get the co2 up and o2 down, and an airlock to get out before testing. Or maybe even just pumping co2 in there. That eliminates water vapor, heat, and varying o2 to co2 conversion.
Later, he might even try to take into account that that insulation is not impermeable. I can’t find the values for anything but water vapor though so I don't know if it’s appreciably affecting it.
@@a64738 im pretty sure the planets dont know the time - it is simply based on the presence and absence of light
ex-professional algae farmer here: That scale up from the pale green "piss bottle" up all the deep green 2 liter bottles was actually quite impressive.
This man algaes.
@@hherpdderp I see what you did there.
@@hherpdderp i sat there looking stupid for a few seconds
I grew clamydomonas reinharditi for hydrogen in school, just getting to 5 liters of healthy algae really isn't easy. We ran a Co2 line in I think. But our hydrogen yield was terrible.
@TrustandbelieveintheLORDgo suck deez at the gas stop
Absolutely love this video!
I'm a scientist who dabbles in algae quite a bit - mainly Chlorella and Spirulina. Some tips and suggestions:
Keep in mind that by adding baking soda (HCO3) to the culture medium, you are providing the algae with an easy source of carbon that will compete with the CO2 being bubbled in from the air. This is why recipes like Zarrouk contain around 20g of HCO3 per litre - they are designed for speedy growth. A solution of baking soda will also leak carbon into the air in the form of CO2 until an equilibrium is reached.
Also keep in mind that photosynthesise will elevate pH; their metabolic activity will slow or even stop until you bring the pH back towards neutrality. Chlorella vulgaris can produce 8 daughter cells from a single parent under optimal conditions, so the pH can rise crazy fast and jump from 7 to around 10 - 10.5 in a day or two.
You might want to try starving your cultures of carbon before using them in your experiment and use dilute HCl to keep your pH between 6 - 8.
Also in my experience the lag between illumination and photosythensis is around 20 - 30 minutes.
Hope this helps - looking forward to part 2 :)
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Spaceship: lack of oxygen detected! You have one minute until depletion.
Me: let me grow some plants real quick !
an emergency oxygen system for in space should have at least a month or two of oxygen.
quite a few people already commented on the day/night cycle of plants, so that's one thing.
Another thing that is affecting your setup is the lights. LED lights are efficient because they produce a narrow range of light. Most LED lights are made to make a pleasing light for us humans, but may be near useless for plant photosynthesis. You need to look into what spectrum of light the algae really likes and see that your LED lights are actually producing that spectrum.
A very good point.
Chlorophylls absorb most strongly in the red and blue regions, for the most common ones in green algae, 420-435nm and 640-660nm range. Accessory pigments gather energy at other wavelengths, mostly yellow and orange range. Green is mostly reflected, thus green plants. White LEDs do a great job with the blue, but not as well in the red ranges, and they put out a lot in the useless green range. White LEDs with red LED supplement might do better.
But another huge factor is simple light intensity. We tend to overestimate light intensity from artificial sources thinking they are brighter than they really are. Sunlight is orders of magnitude brighter. Light is what provides the energy and is often the limiting factor. Someone else with a scientific background noted, the lights don't look nearly bright enough.
@@michaelclark4876 Yep, many factors not covered. Water temp, surface area, density of algae, on and on....A lot of people calling this and "experiment", lol. This is not even close to high school science, however maybe it will motivate someone to do an actual experiment.
Thanks ...learning. I thought that from a non-science standpoint. Because artificial light is not natural light. I don't think there are any solar panels inside brightly lit laboratories to recycle the energy. I know this is different than the CO2-O2 cycle, but since they both involve energy transfer.... I will state again all speculation, non-science based speculation.
Joel's homemade Amazon grow lights were specific enough for him to mention for the huge food grade 100gallon barrels. the specific light wavelengths @michaelclark4876 mentioned DO need to be checked against those grow lights' wavelengths. which intensity are you talking about Mr. Clark? lumens? candlepower? watts?
temperature is a variable too. what water temps does that algae like to grow the fastest at? will Joel need to HEAT or COOL that water?
lifecycle of the algae. what is it like? how long do they live? when in their lives is their CO2 to O2 exchange rate the highest?
what i'm ALSO curious about is Joel's 'food' and mineral mixtures. is he sugaring the water to feed the algae or is it general 'fish guts' liquid plant food? or pure nitrate/nitrogen algae food? if the mineral and 'food' ratios aren't perfect in Joel's water... his algae won't grow/divide/die/eat the dead/divide further etc. at perfect rates.
Joel didn't mention the FLOW RATE and Cubic feet/meters per minute of air he is moving THROUGH his algae reactors as well as the Cubic feet/meters of air INSIDE his 'sealed chamber'. plus... he didn't double triple and quadruple check the airtight nature of his chamber. every. time. he. started. a. test. if any amount of 'outside air' gets in or 'inside the chamber air' gets out... all his ratios and rates are invalid.
concrete is porous! it absorbs water, releases it, it as well as allows gasses to penetrate. did he rough up that section of concrete flooring in his basement, seal it with a polymer coating, polish it, seal it, and polish it again? or did he even lay down a few layers of plastic drop cloths like housepainters use? it didn't look like it to me in this video... he shoved multiple 100G barrels across the bare concrete floor.
this is a pretty fun and funny video... but Joel left out a crapton of stuff!
Interesting experiment, but note that a significant portion of the CO₂ might just be dissolving in the large volume of water, potentially around 1.45 g/L at room temperature. To verify, measure the dissolved CO₂ concentration in the water with a CO₂ test kit, direct sensor, or by calculating it from pH. Consider this in your analysis to accurately assess the algae’s impact.
Was going to reply with this dame comment-- either track the water pH and O2% in the room as well or repeat the experiment with only water and no algae in the tanks to measure the buffering/scrubbing capacity of the water alone. Either way I love the spirit of the experiment, keep being awesome Joel!
Same*
A prime example of why science is hard, if I was doing this experiement I would have missed this variable, well done
@@TheMotlias nah, science is very easy, you're just super stupid
Good ol’ equilibria equations
FINALLY a guy who doesn't quit before reaching the final result, I've seen far to many people end the video with "it is possible but im not doing it" so thank you for going through with it
Little early to say with part 2 on the way still.
Let's hope he did not suffocate in a room full of barrels with green goop in it.
I haven’t seen any videos that quit, but MY problem is when it’s NOT possible, because I ALWAYS get my hopes up, and I can’t STOP being hopeful, because despite being pessimistic, I just think that the thought of it being possible is too interesting and/or cool to give up on believing! Besides, even *I* can’t be negative *all* of the time.
he's earned a sub and a like from me
this
"You gonna keep me alive?"
"eh..."
You can tell, these are actual brothers.
exact same thing I thought LMAO
I am an astrobiologist. And before I get into this video any further than the claim, 6 to 8 plants is an incredible understatement. An average plant produces 5 milliliters of oxygen per leaf per hour. They also produce more or less at certain times of day, stage of their life cycle, light exposures, and temperature. People breathe about 7.5 liters of oxygen a minute. So, if we're talking about average plants in a highly controlled environment, a minimum of 90,000 leaves would be required to provide for one person's average oxygen needs. Algeas are actually responsible for between 50 & 70% of earth's oxygen production (depending on study and types of algea). Even then, dead and decaying algae can greatly reduce the amount of oxygen produced by the healthy ones. And weather patterns affect photosynthesis, as does night. This is a very difficult problem to solve, even for people who's jobs are to solve these problems. There are so many variables that we know but still likely even more we don't fully understand.
Edit: I just finished the video and I am thoroughly impressed with the experiment thus far and can't wait to see part 2! Algae for the win!
Phytoplankton would be more efficient, no?
Algae are phytoplankton.
Are there calculations that factor in the amount of oxygen that the plants themselves use to actually process the sugars from photosynthesis? 90,000 leaves but what if they did not use any oxygen at all, would it be reduced to say 60k or even less? I think one of the thing that people don't realize is that trees and plants produce oxygen but also breathe it as well, just not at the same rate.
@amelliamendel2227 Phytoplankton are a very efficient oxygenator and form the basis for all the ocean food webs. When we speak about phytoplankton, this term includes both microscopic single-celled algae and cyanobacteria. Algae is a very interesting life form. It has been around for billions of years. Our earliest fossilized records for it date to the Precambrian era. Cyanobacteria formed around 3.5 billion years ago. More complex multicellular red algae began forming about 1.4 billion years ago. Freshwater green algae is the most likely ancestor for all forms of plant life we have on earth today.
@cchavezjr7 I am sure that there are specific calculations for respiratory oxygen use in plants, but they are not something I deal with. I will ask some colleagues. I know that there is a net production of oxygen and how that helped us to be here today. I study the history of life, looking at where it first formed, how it evolved, and how it might evolve in the future. This helps us understand more about the effects our planet has on us and us on all life. It helps us to determine if life exists elsewhere and if we send missions to nearby planets, moons or possibly asteroids and comets (if transpermia is a theory we want to delve into), where we would expect to see evidence of life. It's fun to think about ways life could have been different here and what life might look like elsewhere.
Nasa never claimed it would produce enough oxygen. It was a study on household air pollutants, snake plants are good at clearing some of the VOCs in a sealed environment.
Also, water is really good at holding co2 in the water column. Were you checking the co2 concentration in the water?
This could be a major compounding factor, also could affect the PH of the growing solution, and PH adjustment could introduce chemicals that react with some of the CO2.
Water is just great at holding dissolved gasses in general. I'd run the experiment with distilled water, aerated, just to see how long it takes to reach the threshold sans plants.
Not to mention. It looked like the snake plants were just recently split. Freshly turned soil releases CO2. So that likely threw off the snake plant numbers as well.
@@oasntet Exactly what I said in a separate comment. This experient needs an actual control to compare against
very good point, but it's important to know that the dissolved CO2 is equivalent to the CO2 concentration in the atmosphere. they don't CAPTURE it, the CO2 just dissolves based on the pressure off the gas, it's Henry's law. meaning they would slow down how fast the CO2 raises, but it would keep raising forever. also it's something you can calculate, so no control needed.
That is one heck of an experiment. Feels like I'm watching a mythbusters episode
Times ten. No hurry and just more and more and more. ;)
as soon as i saw the sealed room, i thought of their "hold a grenade shut" myth
Same I was getting such MythBusters vibes from this. From the janky setup, to the science content mixed in, and of course the if it's worth doing it's worth overdoing mantra of the experiment. This was peak UA-cam MythBusters style content and I can't wait for part 2
yes
We all think it's really cool! Hope this video blows up it deserves it man. I'm a dropout nerd and your content is so fun to watch, real science done in such a fun, quirky way👍
Incredible diy scientific aproach, inspiring us all, thank you sir!
Probably someone already pointed it out. But snake plants are the worse choice possible in this scenario because they are adapted to first store energy during the day and breathe at night. If you give them light the plants will close their stomata during day to preserve water.
It's often in the list of plants that are good for air quality because they provide that function during the night instead of doing it during the day so they complement the rest of plants but they are not particularly efficient at doing so. Choose bigger plants and fastest growing ones if you want to see a noticeable difference.
I was thinking about light/dark photosynthesis reactions during the video and thinking if the stomas were actually even open.
Also iirc snake plants were good at removing VOCs and other stuff you don't want, but like you said not that good at Oxygen specifically
Not to mention that he needs UV lights, not just regular warm lights for them to use CO2
Also, you can't just keep ordinary plants in light conditions all the time, after a few days they really start to suffer, going yellowish and weak.
They need at least some night, like we do.
yeah you would need to do this test at night in the dark. That is when snake plants release oxygen.
Napkin math:
The body burns ~2000kcal, give or take 500g of carbon, every day.
Spirulina can grow about 25% per day.
So in order to compensate 500g of carbon, you'd need about 2kg of Spirulina at ideal growth condition, ignoring water weight of the cells.
Concentration seems to be around 0.5g per liter of solution so maybe you'd need roughly 4 tons of algae solution per person I guess
still viable if you can convert water in equilibrium, especially given water shells are going to be used in space ships and stations
That's sounds like a lot, but that would only be 2m×2m×1m tank. And that seems pretty reasonable to me.
What would the maintenance of such tank be like? Does the algae need to be cleaned and how often?
4 tons as in 4000 kg?
The energy burned by the body isn't a great measure as not all of that energy is created through an aerobic process, we also don't consume 100% of the Oxygen we breathe in. It's better if we look directly at the volume of air inhaled and the amount of oxygen removed from the air during each breath.
The body needs about 750-800kg of Oxygen per year, this accounts for how little Oxygen we actually consume as a percentage of the atmosphere during each breath, while keeping the air comfortable to breathe.
You can get away with about 16 tonnes (8 adult) of sycamore trees, assuming they continue to grow at a constant rate, they will output ~800kg per year of 02.
The other issue with this question is, does 1 person breathe out enough carbon dioxide to feed that same number of trees.
Spoilers, we don't. A single human will generate about 0.7kg of C02 per day, or ~250kg per year, enough for ~6 trees which can go through a max of 40kg of c02 per year per tree.
While there may be some foliage that is better at producing 02 and eating C02, you'll never get a perfect cycle where a person outputs enough c02 for all of the plants while the plants simultaneously generate enough 02 for the person.
If there was perfect efficiency in that way, we'd effectively have a chemically powered perpetual motion device.
@@jamescheddar4896 we still don't really have a launch vehicle for water transport like that. No one's really built a tanker yet.
Coming from an aquarist standpoint the issue is that air pumps do not really do a good job of gas exchange. its all about surface agitation. if you made an aquarium (any box that holds water) with the largest surface area you could fit in that room, and had a Ton of surface agitation (e.g. a strong spray bar) then it would have worked way better. You needed to manually pump your CO2 into the containers because they didn't have an open source to the air, only what was making its way into the pump.
Yes! As a fish keeper that's exactly what I was thinking. Need longer more shallow tanks.
I'm thinking big, shallow tanks stacked on top of each other with fans circulating air from the rest of the room through the vertical gaps between them.
If proper air stone (wood is really good) is used with strong air pump this setup will be better than surface agitation, just area of bubles need to be larger than top level surface, with my saltwater tank this holds true and air stone is better than surface agitation. Do not spread misinformation.
sounds like a shower head high above a cut in half big bucket would be almost the best..getting droplets in air for max surface area and then great surface agitation
or something like this from Tech ingredients..
ua-cam.com/video/7w4rg3UcsgI/v-deo.html
00:01 The number of plants needed to survive in a sealed room
02:13 Testing the effectiveness of plants in producing oxygen
06:21 Indoor air quality can be affected by high levels of carbon dioxide.
08:28 Even with 12 snake plants, CO2 saturation rate remained high.
12:29 Portable photo bioreactor using small bottles has potential for oxygen generation.
14:58 CO2 levels rose despite operating at reduced capacity.
18:59 Creating affordable algae lighting for tank
20:56 Testing efficiency of algae for breathing needs.
24:48 Exhaling into the algae tank reduced CO2 by over 90%.
26:44 Testing the impact of plant reactors on oxygen levels in a sealed room.
Crafted by Merlin AI.
Can I genetically engineer my skin cells to have chloroplasts? I understand it's not easy being green, but you get to go outside for lunch
You would need several orders of magnitude more surface area than you have for this to work, from what I've heard
Problem is.. what are you gonna do witht the carbohydrates. You'd need to burn them that excess fat and sugars.. By exercising.. Generating more carbon dioxide to turn into air
Our skin surface area is incredibly small compared to whats needed. Basically it wouldn't make a dent. sorry man :/
You would need as much surface area as the food you eat needs to grow
@@eh9618 He uses way more of them just sitting in the room, he would just use them up no problem
So I'm a microbiologist working on microalgae and the reason for slowing down of o2 production is actually the increase in o2 will inhibit the rubisco to function optimally actively preventing co2 from being converted into energy.
Yes and what about blowing in a tube that goes into water? Doesn't CO2 naturally dissolve in water?
@goku445 so the co2 will dissolve a little but realistically the rate of gas exchange is extremely low. So if you are gradually reducing the concentration, amount of co2 dissolved will decrease
If you find a microbe that never farts that likes to only eat plastic you will win the nobel prize, happy hunting.
I was going to say isn't algae what provides the majority of our oxygen
Heh heh, reminds me of my college days. I took a intro the plant bio and do remember them saying rubisco is one of the most inefficient enzymes out there.
One part of the experiment you might not have considered is the moisture content of the soil the plants are in. They are going to be most efficient when they have ready access to water, and since snake plants are succulents, people often leave them dry for too long.
I also imagine, they also are more efficient at scrubbing carbon dioxide as the concentration increases.
@@weaponizedemoticon1131 Yeah, that's true.
Also, he should have used some of the grass species, or the paulownia trees. These species have a unique photosynthetic pathway dubbed "C4" (no, it's not explosion related). This pathway essentially makes the photosynthetic process twice as efficient at gathering CO2 from the air. Look at species like "Pauwlonia tomentosa" or "miscanthus gigantius". They can reach heights of 10-15 feet in a single year of growth!
Good point, I'm not a plant expert but wouldn't actual sunlight make the plants more efficient? That and spreading out the plants would probably help
@@realzakariax I suppose it would depend on the absorption spectrum of their chloroplasts vs what the light produces.
@@realzakariax Real sunlight could help, but artificial lights are just as effective, provided they are intense enough and have the right wave lengths. Those coloured grow lights you see on amazon are mostly made like that because they are cheap, and not because adding blue and red seperately actually makes a difference. As long as it is a mostly balanced white light, it is just as effective as sunlight.
This was cool. I know I’m not the only one who thought that would be the perfect hotbox.
Holy shit. I kept thinking the video would end but you kept doubling down!
Mate you are insane in the best possible way
Thank you
yeah this video was so refreshing! ive seen people literally just stop at the zz plant phase of this experiment and it's SO frustrating when they give up
would have been a pretty boring video if he didn't find some kind of success...
This video is actually nuts. Even more barrels!!!!
Yup...x2
Now I have to subscribe to see part 2!
That study claims the algae needs a lot of surface area exposed to the air. They weren't in barrels. They were in shallow pools.
Yeah surface area seems important
Is that not why he was pumping air through them?
@@zinklink7953 The important factor there is energy, ie light.
I wonder if an algae waterfall would work well
Cody’s Lab ran bubbles through tubes of algae.
"What if I need to poop?"
Plants: "Please do."
"Please doo doo"*
@@tjken33💀
i aint know plants was down bad like that
Here's another one I thought up
Animal: [does their business nearby]
Plants: "This is some serious gourmet shit!"
@@omegahaxors9-11 ahh i see what you did there lmao
The Russian research on algae refers specifically to exposed 'surface area'. The same amount of liquid/algae in kids pools instead of small bottles, would have massively increased the surface area. This may have made a significant difference.
Also algae thrives better in sunlight.
@@kellyschlumberger1030 Yes, like all plants and protists, they require red and blue light. Not white.
@@-Deena. white light contains both red and blue in its spectrum
@@onlyme0349 Yes, I do know that! However, intense blue and red light is more effective when concentrated.
"Surface area" is a proxy for gas exchange and light availability. The bubbler takes care of the first one. I think the main question here is whether the light sticks are sufficient. However, open-topped pools definitely would not have been a better option in such a small room.
It’s crazy how all of this algae all came from one tiny vile. Insane how efficient nature is
Let me quote Dr. Ian Malcolm "Life finds a way".
I've seen a 100 acre lake go from basically clear to pea soup in a matter of days after a big summer thunderstorm (lightning strikes knock nitrogen out of the atmosphere which then fall with the rain in the form of nitrates which feed the algae), it's crazy how fast they can multiply
There's no more powerful force in the universe than exponential growth.
I'm sure if you filled the oceans with freshwater it could become a giant algae pond in a short amount of time with the right conditions.
@@DjDolHaus86 that would have to be one hell of a lightning storm, i'd guess the major contributor of nitrates to the lake was just storm water runoff contaminated with fertilizer or waste.
@@DjDolHaus86Also during big storms if lighting strikes on the water hundreds of fish and millions of tiny lifeforms tend to die, that also hugely spikes the nitrogen levels of the whole lake and will throw off the balance giving algae the perfect breeding ground to completely take over.
When I was a kid I always wondered why scuba divers didn’t just have a bonsai tree in their scuba tanks. It was when I was older I realized they didn’t produce much oxygen, but the whole how many plants to offset a human has always intrigued me.
There's no light in a scuba tank.
@@jasonsmall5602 starts carrying battery packs for sunlamps
It's not the number of plants, but the weight, as part of the mass of the plant is the carbon, this portion of the mass has to be increasing by the mass of the carbon in the exhaled air... so we're looking at maybe around 10g of carbon per hour. Different plants in different conditions will have a different portion of the weight being made up by that carbon, most of the weight is probably water, so... until you can see the weight of the plant growing by 1 gram every minute, you're probably wasting your time. The reverse is also true... when you exercise and lose weight, this weight loss is breathed out as the carbon and water in similar proportions. So if you breathe in and out of a large bag, measure its weight gain, that would give you a closer number for what you would expect the plants to need to grow, as this includes the water part. Think of the condensation when breathing out onto a cold window... that much water has to end up in the plant as fast as you breath it out.
Wow. We planted.
*We can calculate the absolute minimum required energy input from first principles:*
Max efficiency of white LEDs approx. 50%
Max efficiency of algal photosynthesis approx. 8%
Human resting metabolic rate approx. 100 watts
So you'll need *at least* 2500 watts worth of LEDs illuminating your algae to keep up with your exhaled CO2. I think the barrels probably weren't lit brightly enough and a lot of the CO2 absorption you observed was caused by the CO2 just dissolving in the large volume of water (like watered-down soda).
human gets energy from food not oxygen
@@alen91071 Human bodies get energy from the chemical reaction between food and oxygen (oxidation). The amount of oxygen required to support our metabolic rate of about 100 watts (100 Joules per second) is directly proportional to the amount of food oxidized by our metabolism per unit of time. The reciprocal principle holds for photosynthesis: every gram of emitted oxygen comes with a proportionate quantity of carbon-based biomass.
@@alen91071let me explain for you simpleton. You know how combustion engines work right? gas is carbon food for engines and food is carbon food for humans and nether can burn without oxygen and the byproduct is carbon dioxide that is chemically bonded when oxygen reacts with carbon giving off energy.
and then plants use sunlight to knock carbon off co2 leaving carbon in the form of sugars and starch.
@@lukekambic3536I agree with that oxygen required to suport metabolic rate is proportional to energy produced by body. Resting metabolic rate is measured as heat of a body. My problem is how did you convert 100 watt of heat to a 100 watt of luminescence. In your claim human gets all energy from oxygen ->algae ->light source.
en.wikipedia.org/wiki/Resting_metabolic_rate , en.wikipedia.org/wiki/Weir_formula
@@alen91071 I was only aiming for a rough estimate of the *minimum* energy requirement. When a human is at rest all metabolic energy ends up as heat. Efficiency of photosynthesis is measured in terms of the amount of biomass an organism can produce using a given number of photons of light. In the case of this experiment, the quantity of biomass produced by the algae has to roughly equal to the quantity of biomass (food) that was metabolically oxidized by an animal/heterotroph to produce the CO2 that the algae absorbs. Hydrogen also plays a role in all this (carbohydrates/photosynthetic splitting of water), but the factors should mostly balance out since biomass from different organisms tends to have broadly similar C:H ratios.
You should try one of those pots that I think expose the roots (?). As most of oxygen comes from roots too apparently, or at least some of the pots I'm thinking of claim they give 50-100% more oxygen.
This is fantastic! About a decade ago, I wrote some scifi stuff where people had algae air scrubbers. They would also extract the algae from the tanks, and freeze dry it as a food source. The system was about 5 feet by 10 feet by ten feet in size per crewman. The extra size was for automated processing machinery, and i felt it was 'realistic'.
square cubed law. if that is a 5x10x10 cube. that is 3740.26 gal. about 75 drums. he is experimenting with 4.
Fascinating.
I think we're actually frighteningly close to your writing becoming a reality! Though, you wouldn't be able to use the extra algae grown as a food source without also inputting something back into the system. Human waste might work, but it depends whether the algae (and whatever other lifeforms are in the scubbers) can digest it completely.
Those in this thread, you might like Isaac Arthur, a "futurist." He has done dozens of videos on how we could colonise moons, asteroids, other worlds, create artificial worlds, harvest energy from stars while using them to move the entire system, etc., including Fermi Paradox answers.
I can't wait for Part 5 of this series where Joel is making algae jerky in his basement spaceship.
Former algae grower here, 2 things I should mention. You should have done a control of pumping the air you exhaled into just room temperature water. Water does have a slight ability to dissolve CO2 turning it into carbonic acid slowly lowering the ph of the water. This is all a factor of the water temperature, starting ph and the airflow moving through the water column. It will get saturated at some point but it is surprising how big of a carbon sink plain water can be. The relative short amount of time you spend in that room would also give skewed or frustrated results. Also like plants, algae have a cycle where they scrub more CO2 (usually at night) vs produce oxygen (usually in sunlight). But that all depends on the algae strain and feeding conditions.
Ah yes. I thought I remembered that plants produce CO2 vs O2 depending on the light /time of day, and that for the plant I was looking for it was O2 at night. I was looking in the comments for it :D. Good to know I am not imagining things.
CO2 also sinks so you would want the air intake on the floor.
Former algae here, I agree.
Studied chemical, physical and microbiological analytics, had the same thought!
Plants need Carbon to grow, and use photosynthesis from light to separate and concentrate Carbon and Oxygen. The more CO2, the faster the growth, with the lights on. No CO2 needed during dark periods.
During the dark periods seems to be when the plant puts out the most Oxygen.
Next time he'll have to try just the opposite. Or do more research on the topic..?!🤔👍💯✌️
The research by the russians said, that it should be roughly 80 sqft of exposed algae. Your algae tanks aren't being used fully. I think you are going to need more movement inside the tank to expose more of the algae to CO2 rich air (more air pumped through it or other ways to expose more, stirrer, etc.)
Imagine doing all this and not having understood the papers supporting these claims 😂
@@phonoticalWhy don't you think he understands it? He basically says this at 22:30
@@radeklew1 you saw the video
if he opened the tops to bubble exposed it would seriously help
that's why they decided to use simple electrolysis of water to produce oxygen. submarines and the space station have been doing this for 50 years. He could have spent 20 bucks and just vented the c02 from the floor and the hydrogen from the ceiling
I hate to break it to you but you need good old incandescent lightbulbs to get plants to do photo synthesis at peak efficiency leds or “grow lights” don’t work well or at all
One thing I noticed is the lack of baffles. The bubbles aren't making contact with as much algae as they otherwise could. With baffles in the liquid it would slow the bubbles down instead of going straight up and only really mixing the top layer at best with comparatively narrow cones of interaction between the bubbles and algae, which should allow for a longer duration of interaction.
The bubbles do relatively little regardless
if its anything like fish, the bubbles are there to help dissolve oxygen in the water
Also a propeller based agitator motor powered to create more momentum for turbulence. But them we can get into temperature and pH sensing and control. There is a limit to this DIY testing. Baffles is a good cheap improvement
The bubbles are meant to dissolve into the water. For aquariums, there are special micro-bubble aerators that make bubbles so fine they never make it to the surface. (I use an air trap instead. Basically, an upside down cup holding a small amount of CO2; as it dissolves, the pocket of CO2 disappears.) For his setup, regular airstones will work just fine. It will have to cycle the room air multiple times, but that's OK. You'd want that to help push out O2 as well.
As a quick back of the envelope calculation, a human using 2000 calories coming from a diet of 50% carbohydrates, 25% fat, and 25% protein releases roughly 800g of carbon dioxide, which is equivalent to roughly a half kilogram of starch/cellulose/etc. The algae tanks are absorbing a lot of biomass!
I am assuming that the 800g of carbon is per day correct?
I corrected your maths, "Based on a quick back-of-the-envelope calculation, a human consuming 2000 calories per day from a diet consisting of 50% carbohydrates, 25% fat, and 25% protein releases roughly 323.7 grams of carbon dioxide daily. This amount is equivalent to about a third of a kilogram of starch, cellulose, or similar substances. The algae tanks are absorbing a significant amount of biomass!" Phytoplankton would be much more efficient for this purpose
@@amelliamendel2227Are you sure about the 323.7 grams of carbon dioxide?
I did a simpler calculation using 1 glucose + 6O2 needing 6CO2 + 6H2O
Assuming 4 kcal/g for glucose and 2000 kcal per day, that's 500 grams of glucose per day, which require about 733.3 grams of CO2
Smarter way of calculating this is just trying to make a system that makes the equivalent calories you consume. That would be the true equilibrium. Plus you would get enough food to maintain yourself.
@@yusuftekten2652 You would need to always exert yourself exactly the same amount every day without any variation; better to just allow for a range by having some kind of buffers. Plus it would require a lot more investment, research and adaption to fully recycle your urine and feces back into food and clean water to make a full closed loop.
Snake plants only exchange gases at night due to their Crassulacean acid metabolism (CAM) so you need C3 or C4 plants to absorb co2 and release oxygen when lights are on. You could use Bamboo or Cannabis since those are very fast growing plants in the right conditions.
The comment I was looking for. Snake plants ARE CAM plants!
Literally grade school biology knowledge .. Very disappointed in this experiment.
Dang. You beat me to it.
@Root_boy I'm jealous of your grade school I had to take bio1000 in college to learn that lol
I must have missed that in grade school
21:50 I think it's pretty cool too. Thanks for doing this.
I like that this is a guy that didn’t entirely know what he was doing but tried his hardest to learn and that’s the type of casual drive that I like
me 2
my man reinvented carbon capture .. respect
Completely clueless.. did the science entirely wrong... Extremely entertaining
Or he just made dumb mistakes that could have been avoided by a few google searches and common sense
@@trealin4730 Sure, but that would have ruined the fun of the video. This is made for entertainment dude, and it would get the same end result either way, this way is just more entertaining to watch.
I really enjoy how quickly this became outrageously complicated.
Complicated and no scientific. ;)
Right? I have snake plants in the back yard, and thought "oh, ill get some in nice pots and bring a few in." that quickly turned into "oh, well my house isnt big enough" to "well, a green lava lamp thing would be cool" to "oh, well I only have the blue 50 gal drums", then back to "oh, well my house isnt big enough..... whats for lunch?"
Plot twist. Never made it past the first test, the rest was just hallucinations
Lol
Lolo
his brother found him passed out covered in algae
Bro breathed in too much algae 💀
He's actually in a coma and the entire thing was just his dying fever dream.
I used to be super into this exact kind of bioscience.
The biggest problem is never not going to be the surface area of the algae and consequently the amount of light they get.
Some of the most effective setups I've seen use either very long 2-3 inch acrylic tubes, or large acrylic windows sandwiched together, laid out like solar panel arrays.
The solution, then, is paneling the hallways inside/outside the station with thin (~1-2inch thick, tops) tanks. Add a thin air line for a micro-bubbler, and you have more than enough surface area on a spacecraft to make that oxygen. The only long-term problem becomes cleaning/recycling your algae.
Strings of LED directly imersed in an Algae vat with mirrored walls seems the best solution for an enclosed space. Trying to collect sunlight directly onto plants of any kind is a fools errand, a spacecraft would collect solar power from thin and high efficiency panels and then produce maximally photosynthetically efficient light resulting in minimal waste heat problems and minimizing pressurized volume.
Maybe a better medium for the light, immersed in the algae, could work? Like plunging a large amount of dense, clear, open cell foam into the algae. Could be made of acrylic. Maybe in combination with lining the barrels with a reflective surface? Something like that?
I don't think the problem is the plants. I knew it wouldn't work right away just looking at the lights in the first setup. In order to photosynthesize away 1 human worth of CO2 (about 1kg O2 per day), you need like 2500 watts of grow lights, minimum. Doesn't matter what kind of plant so much, cause there's no free lunch. Can't turn CO2 back to O2 without energy. Also, the plants, being alive, will use up O2 and output CO2 just like all living things. They can only do the photosynthesis with enough light.
The real variable isn't the gallons of algae mix, it's the extra grow lights and pump/scrubbing. I suspect it can be done with fewer barrels, just more concentrated, if you put like 5 of those light sticks in each one.
@Brainstormer_Industires Finding the optimal wavelenghts may also help, the right colours really make a difference, and the intensity as you say
@@DG-iw3yw Yes, more efficient LEDs that only produce the right wavelengths would lower the electricity requirements! However, filtering doesn't help, since that can only absorb energy.
People who say "there's no such thing as a free lunch" when I start dating their mom and she offers me homemade meals:
Yea i thought so he is not using proper growing lights
@@DG-iw3yw yes he should have used violet collerd light made for growing
As a former U.S. Navy Submarine sailor, There is a reason the submarines have chemical C02 scrubbers. Even though the submarine has oxygen generators, C02 will continue to build. I guess the Navy decided it was not feasible to have a few hundred gallons of algae per sailor on board.
Oh, I have wondered about plants and oxygen generation since I was around 10..I saw a movie (comedy,1969) "Hello, Down There", made me want to build an undersea habitat....Maybe joining the Submarine Service wasn't so strange after all.
Well, I think there's the fact that on a sub that there are what, 100-150 people on board? Then there's every piece of machinery running, electronics breathing, food being cooked, all kinds of factors going on there...
The other difference here is, on a sub, you get to come up for replenishment, in space, you might not get that... Algae will theoretically, grow as long as you're breathing to feed it...
👍
The 02 generators get it by electrolyzing water, not removing it from C02. The CO2 scrubbers are also rechargeable and not really "chemical".
@@obsidianjane4413 there is a chemical compound that can smolder for a while, and it’s off. Gas is pure oxygen, that’s one of the things they used to generate more oxygen aboard a submarine. It was a whole video on the subject of oxygen generation, and CO2 scrubbing on UA-cam. You should go check it out.
I remember that movie !
The surface layer of the ocean is teeming with photosynthetic plankton. Though they're invisible to the naked eye, they produce more oxygen than the largest redwoods. Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean.
Part 2 done yet? I can't wait!
"Hey, you're the weird hat guy that made that spider jiz wrist thing!"
Succinct
😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂
@@JoelCreates damn, guess he'll be the one coming now.
@@PMtoAM no i think that was the thing on his wrist
@@ThatNerdGuy0 ohhhhhhhh
i didnt know spider man was x rated
Knocked it out of the park with this part 1 Joel! The documentation, story, purpose, and soul in this video is epic!
This video is quite Epic
Awesome project, I love how the algae containers just keep scaling up.
My guess is that you are going to need at least 100 times as much light as you've got. Light is what powers the conversion, so you could have a whole ocean of algae and it wouldn't make enough oxygen if you don't provide enough light.
hi, i really appreciate your work, i want you to help u in this project.
here is the things you need to know.
to survive 1 human we need 800 grams of oxygen per day (660 liters).
so in order to get that much oxygen with the help of algae.
we need 200 liters (50 gallon drum) of water, with 3 grams of biomass of algae per liter. which is equal to 600 grams of biomass. which produce about 960 grams of oxygen.
in order to grow 3 grams of biomass per liters you need more aeration and more lighting. and another important aspect is nutrient concentration . the required concentrations are :
1. 30 mg of potassium nitrate or sodium nitrate per liter.
2. 3mg of phosphorus (Dipotassium Phosphate or Dipotassium Phosphate) per liter
you need to add these nutrients every other day or every 2 to 3 days depending upon the growth
i hope this data will help you in next video.
if this data helped you, don't forget to reply.
thank you.
When people joke about those algea tanks that were shown and proposed to be put in cities and said "why not ya know trees these are ugly" this is why, trees are amazing at cleaning up the air but people really forget how much ocean life is also doing it and its crazy efficient
The reason trees are nice in cities is not the oxygen production, it's the shade and evaporative cooling they provide, not to mention the psychological benefits.
Then there is all the other cool stuff that is being done with algae too like making bio plastics.
It wouldn't be that horrid if instead of simple cylinders, they had aesthetically pleasing shapes. You'd basically get a translucent sculpture with green water and bubbles swirling it like some kind of retro-scifi movie set. At least it would be a nice decoration. Probably quite expensive to run though.
@@inv41idBoth
Points for trees: Trees in cities are eventually giving lumber when they're taken down and replaced with younger trees. Trees have little maintenance apart from the occasional branch removal / risk assessment. Trees also offer shade as mentioned by inv41id, serve as habitat for birds, keep the soil healthy and offer shelter for other critters.
Points for algae: Schools can make science interesting and give this kind of project a massive boost in efficiency by putting it through many hands/iterations/climates.
I'd love to see a basic setup for people to make, with sensors for the necessary chemicals/elements, an easy way to upscale a setup or sideways scaling (horizontal), semi-automatic resetting and maybe adding a mechanism that selectively composts the surplus algae (that no longer grow).
Hey brow, I worked with Chorella when graduating (Chemical Engineer).
I'm not going to spoil the fun for you, but to give you a hint:
* Search for the optimum light spectrum for your Chorella sp. (it's in nm of wave length) to absorb and actually produce O2.
Also, be aware that Chorella grows WAY TOO FAST. Meaning: it multiplies its cells in numbers in a few days, then caps it, then start dying A LOT! Search for the cell number growth curve (ps: the green color you see is misleading).
Congrats for your abservations, you've been doing such an Amazing Job =)
exactly what i was thinking as an engineer here: wave lenght of the light and how much "room" does the algae have to multiplicate since it needs to multiplicate to make oxygen.
That being said: the guy is amazing.
it can die?! So why people grow it? It seems labor intensive to keep cleaning tanks. Better to have trees/plants, right?
@@fashiharz8584 No, man. Algae is the way to go if you want oxygen "from nature".
Ideally, to artificially create/inject oxygen in a room you would use oxy-redox inorganic reaction, they are way more efficient and easier to control.
The oxygen available on earth is available abundantly because of algae.
Trees are actually useless. They consume what they produce except for a short period of time (photic compensation point). It's hard to make trees/plants/complex organisms to produce oxygen enough to make an environment breathable, way to many space, way to many variables.
As a matter of fact, 99% of those so called "env scientists" know absolutely bollocks about biology.
Trees have other roles in the ecosystem, oxygen wasn't, neither will never to produce oxygen for other living creatures.
@@fashiharz8584
PFR, is the answer for that question.
Also known as continuous flow tubular reactor.
so plants dont give oxy, but algae does. Thats what this video shows....Or you use additive.
I like how you just progressively revealed that each test was a fakeout, and that the "real" test was just starting, before revealing your ridiculous new setup you've been working on the whole time. You got really invested in this whole thing.
This isn’t even my final test form
I think it's really cool too. Well done. Thank you for doing this.
Here's the things I'd do to improve your setup:
1. Connect them in series rather than in parallel. Pump air from the room, or the mask, into the first tank, then the output of that tank into the second tank, and so on. This gives the air with higher CO2 more time with algae water, and thus more time to be cleaned.
2. Introduce a counter-flow by pumping the algae-water from the bottom of the last tank into the top of the second-last, and so on until the first, then pump from the bottom of the first tank into the last tank. This way, the algae processes its CO2 encountering higher and higher concentrations and then gets a rest; meanwhile, the CO2-saturated air goes through passes of fresher and fresher algae-water before being released back into the room.
3. Ideally you'd want small-diameter, tall bubble-columns with your lights and hoses in the center, thus ensuring maximal utilization of the available algae water by reducing the possible paths the bubbles can take, and thus algae-water that might not see many bubbles, and also having most of the algae-water near the lights, giving it the best ability to use the CO2 bubbles it encounters.
4. It would be possible to flow the algae-water over specialized 3d printed vanes to maximize the surface area of the water in contact with the air, and blow the air through the vanes rather than pumping it. This technique is used in Carbon Capture Storage with lime water rather than algae, to capture CO2 from the air.
My man got sold on the snake plant oil
underrated
This comment is underappreciated
Good one!
😂
If I'm ever trapped in a sealed room and can instantly grow plants, I know I'll be OK
Bunker life
@@epicthiefplants need fed too lmao
@@TheNebulaEffectMinecraft easy just put a few drops of pee in them and pray you have a healthy microbial flora to break down the ammonia into nitrogen
@@TheNebulaEffectMinecraft it's effective but nobody in the bunker will thank me for dropping one in flour pot. Lol
Access to the supply chain may be needed lol
I admire your dedication and effort in this project, dude.
"Who has this many houseplants?!"
Me: *slides down in chair*
Same. Lol
Plant mommies/daddies rise up.
My thoughts exactly 🤣 I would have 20x that minimum
I have 17 sweet potato vines in my kitchen window.
@@FLYGTRVICdon’t mean to be rude but that 6-8 plants by nasa is false it’s never been published by nasa it is misinformation that was spread online.
Another huge variable is the amount of light, which shouldn't be overlooked
yes, and the plants use the infrared spectrum
@@PinkDiamond-2000plants specifically DONT use IR. They reflect it more than anything else. That’s why trees are soooo white in infrared photography.
That's what I was thinking the entire video. Skip the small tanks, and place 5 light setups in each of the large tanks. Also may need to reduce the amount of Chlorella in each tank. Not only do they block light from each other, but as waste products (including oxygen) build up in the water, it likely reduces the efficiency of CO2 scrubbing.
size of the plants also plays a huge role
I'd also consider the plants were probably stressed during transport which can factor in on growth rate and also consumption rate. The plant's I'm familiar with use more co2 during the flower stage, so that's something else to consider. I'm no proctologist but I'd probably seek the advice of one before testing.
At so many different points in this video 99% of content creators would have just given up and called it a failure, so glad that this amount of hard work blew up for you.
Just a tip on your door. They make a sticky zipper for sheets of plastic. This might help with sealing the room. Another idea, PVC skeleton cube and just heat shrink the whole thing in plastic like your window. Rope Lights might not be a bad way either. Not sure if they provide the right type of light.
I'm an amateur game developer and writer and one of my game concepts was a bunker miles underground that had a "Green Level" to supply food and air. I wondered how much plants per person I'd need in the game to make it realistic. Thanks.
so ig based on this you'll need to have the green level be many times larger than the others
try figuring out how many plants it takes to feed the people in your bunker and that should overshoot how the CO2 problem !
Exactly the amount needed for food...a bit less considering you own weight
Plants only really absorb CO2 while growing, so calculate the growth mass of the plants multiply by about 0.8 and you get a very very rough number of how much CO2 is removed. You can find how much CO2 an average person produces per day, and do a fast calculation on how many plants you need. Just as a warning it's an extremely large number as you can not calculate the mas of the plants, only the mass of what is growing, which is a very small amount of the total mass for most of the life of the plant.
oxygen not included ?
The air pump helps more then you probably realize. Water also sequesters co2 by desolving it into carbonic acid. Using the air pump increases the consentration inside the jugs, forcing the CO2 to be sequestered and desolve. If you checked the acidity of the water before and after, you'd see it's grown slightly more acidic.
TLDR: ph monitor, swap cooler, more lights, stick to the co2 clock, More videos like this please
Quite an interesting hypothesis with CO₂ dissolving, very much needs a test. Also it might also be good to put the light on the walls of the tank instead of the middle so more algea get it. On the fountain idea, "common sense"(quote because ye it can be quite unreliable) would say it's better for them to have both CO₂ and light at the same time, but I suppose the reaction not being that fast could make it not a problem.
Plants also produce CO² at night...
Correction on one of your sentences. you 100% definitely die from missing o2. But our bodies are designed to react and realize it's dying only due to co2 oversaturration.
In that way, if you had no o2, but NOT an abudance of co2, you can die without ever knowing you are.
That's where horror stories like, a guy dies after kneeling down to tie his shoe, not realizing he knelt down near a sulfur pool pit, comes from.
@@runed0s86
Plants always produce CO2, but consumes more when there is light
🤓
This is awesome. I have been wondering about this for a long time and remember when I saw that movie I just felt it wouldn't work with so few plants and in such a large area. I was a kid also. Great work. It was also entertaining. Thank you
I'm fascinated by this! I did some research and maybe this would be helpful for your next experiment:
1. To meet the daily oxygen requirement of 550 liters (approximately 735 grams of oxygen), you would need around 24.3 gallons (92 liters) of Chlorella vulgaris culture.
2. Algae, like all living things, undergo a process called respiration, during which they break down organic compounds (produced during photosynthesis) to release energy. This process involves the consumption of oxygen and the release of carbon dioxide. Essentially, algae take in oxygen from the water and use it to oxidize organic molecules. As a byproduct of respiration, carbon dioxide is released back into the water. This is the opposite of photosynthesis, where carbon dioxide is taken in and oxygen is released. This process occurs during hours of darkness.
3. I'm not sure if your keeping your Chlorella Vulgaris under lit conditions 24/7 or not, but it may allow for more efficient photosynthesis during your next experiment to give them at least 8 hours of darkness before starting the experiment.
I can't wait to see your next video!
Is that 24 gallons of culture or overall with water? I have an idea, but it depends.on whether it can be done in a 55gallon drum or needs a swimming pool.
@totallylegityoutubeperson4170 The culture volume includes water (the medium for algae) and necessary nutrients. 24.3 gallons would assume having achieved carrying capacity (the maximum population size of a species that an environment can support indefinitely).
this is EXACTLY the type of content that we want to see
agreed!
1:37 i live in cleveland and i took that with full offense
Joel: "How many plants do you need to breathe?"
Joel about 5 hours later: *casually terraforms mars*
I thought you were talking about me
@@joelroy9221 I was.
Awesome experiment! Subscribed!
Photosynthesis requires blue and red wavelengths. There are lamps specifically for this. It would be more efficient than using white lamps.
Photosynthesis happens from 400-700nm and is not limited to blue and red. Why do you think high end led grow lights are white? They use a full spectrum.
@@johnjohnson8424 Er, no they are blue and red. Do a search for "horticultural lamps" and you will see that they intersperse blue and red LEDs of wavelengths tuned to the plants requirements. It is a waste of energy illuminating with green, because the plants reflect green. To our eyes these lamps appear purple, not white.
Some lamps do also include white LEDs, (among the red and blue LEDs) but that is for growing flowers. I never saw a flower growing from algae.
Curiously, on another channel there was discusssion of using green light to cause water to evaporate more quickly. Which is precisely what plants would not want.
@johnjohnson8424 Not green however, plants hate it because green wavelengths evaporate surface water very fast.
@@GM-vt6isit makes sense. Plants are green, it means they consume red and blue and reflecting green back to our eyes
@@GM-vt6is "green wavelengths evaporate surface water very fast" I only just found out about this. How long has this been known?
Social media post was way out. Going to the primary literature:
...249 potted Dracaena lutescens would be required to completely remove all of the exhaled CO2 from a single occupant, in a completely unventilated room. This number is slightly reduced if high light adapted Howea forsteriana under 350 micromol PARm−2 s−1 (VERY bright lights) is considered; due to its greater leaf area, 206 individual plants would be required. These estimates are obviously impractical...
From a paper on this very topic:
Torpy FR, P.J. Irga, M.D. Burchett (2014) Profiling indoor plants for the amelioration of high CO2 concentrations. Urban Forestry and Urban Greening 13: 227-233.
A large green wall (4-5 m2) with plenty of light would work on paper...
Great video!
350umol is bright but not crazy light. It's about average for naughty lettuce. Sunlight can peak around 2000umol. I have an SQ520 quantum par meter and designed LEDs for nearly 2 decades.
@@N4CR Agree with that. We decided on 350 umol by walking around a university building with a light meter: we recoded it about a foot in front of a feature light. No reason why it couldn't be used for a green wall...apart from being a bit glary for occupants. We also use naughty lettuce light systems in the lab :)
People always talk about snake plants, but anyone who’s owned a snake plant knows they have low metabolic activity. They’re the turtles of the plant world. A faster growing plant with more photosynthetic activity would in theory work better I feel.
Doing a little Google-fu... a typical plant leaf produces around 5 mL of oxygen/hour. A typical human needs about 50 L of oxygen/hr. So that's 10,000 houseplant leaves, or somewhere between 500 and 1000 houseplants.
so does that mean that if we have less than green team than (population of earth*1000plants) , we slowly die?
no one is measuring/monitoring this now globally 💀☠ fuuuuu
Yes i agree, you need something that grows quickly and aggressively (the same reason that algae was selected)
The only reason i could see going with plants instead of algae that i could see is if you wanted dual purpose (food, emotional well being) and of course oxygen production.
I also think that having powerful lights in the photosynthesis spectrum and as powerful as possible would help greatly. (Energy input)
@@cajunboy67 Another thing is, 1/2 the world is in darkness 1/2 the time (nominally). The Creator of this world is pure genius. Am I the only one to realise that?
@@Roq-stonewhat are you trying to say?
Oh my! This setup is amazing. I really enjoyed the video, so many useful tips. I really appreciate your use of limited space in the layout. Ever since purchasing a portacapture x8 from Sweetwater, I am all in. Top notch all the way. Thank you for making it personal.
You've basically made an episode of Mythbusters. It's awesome work what you've done.
What a GREAT brother! To just sit there and make sure you don't die!
How is there no reply’s?
@@KermitTheFrog000 whats there to say other than we all wish for cool bros like that in our lives
making sure you dont die
Who else would he mock then?!
My brother would just keep telling me I'm going to die
i asked my father this question about two weeks ago and now i am surprised to see a video of the exact inquiry i asked to my father
What did he say?
@@WildVoltorb "Let me out of this box... can't.... breathe...."
@@chrisbalfour466😂😂
This is not the sort of content I usually get of my feed but I'm glad I did.
Can't wait for part two
"I don't know if this video will do well, but *I* think it's cool" is the line I want to know is running through every UA-camr's mind when making a video.
Co2 sinks my guy, put the meter and the fans on the floor
You could add nets horizontal inside the barrels so that the bubbles get stuck to them and spend more time inside the water and get more exposure to the algae. That could also improve the effinency.
Lovw to see someone go all the way with their experiments instead of just stopping at the first few tests. I was invested the entire time, love it!
1:43 watching from Cleveland... On the toilet. Right now.
Cleveland isn’t even that much more “harsh” than any other rust belt city.
@@pokechatter agreed
I applaud any experimenter who concludes with more doubts and questions than answers. This is as it should be.
This was an extremely well made video and experiment! The amount of effort was insane! That DID NOT feel like 27 minutes can’t wait for part 2!
Didn't feel like 27 minutes
@Wunba
Now I expect you to do the same in Minecraft
WHY THIS DOES NOT POPULAR
Thank you!
Hey!
So turn the lights out for half the time. Go back to the capsule. And remember (the crebs cycle) botany college level books are there for reference.
He was worried that no one would care about this video? It’s only been 20 hours (less than a day) and it already has almost 250 THOUSAND views. His second most popular video (of the ones that have only been around for a year) has 1.5 Million. If we assume that the views on this triple in a week (which is a very fair assumption) he could have half of those views in just a WEEK! He could have half of the views of one of his most popular videos in only 1/52 or 02% of the time! This video is definitely blowing up! Your work has payed off
Also, you should include a second test in your next video of this with algae in pools instead of barrels; It’s been suggested quite a bit.
It's like a hot girl posting a sexy selfie with the caption - 'I'm so ugly, ughh'.. Fishing for compliments or attention.
Plants do pause their photosynthesis and stuff if they’re shocked by movement and stuff. It also depends on light sources.
yep, that was also not helping him, but the amount of plants was simply nowhere near enough.
They only pause it if there’s no sunlight for them to photosynthesize… not “movement and stuff”
@@ZaeOSWS most photosynthetic organisms tend to slow down after a certain point. You don't usually run grow lights 24\7 with many species, they need some time to "rest". Algae can take more hours than most plants, but some species still at least slow down their CO2 intake for a while.
@@aggonzalezdc lies, I’m literally a plant lmao stay human bozo
@@aggonzalezdc The other problem is different types of algae work best with different types of light. Frankly the biggest problem I see in all this is the light sources he is using. There is a reason the professional light source was 2000 dollars a pop. It probably provided a much broader spectrum of light than his DIY version. Is also the reason that pot farmers use special grow lights when they farm inside. The light matters a lot more than he seems to realize.
Something for your consideration, as an avid fish keeper one of the first most important things you learn about keeping cichlids is that they have a high demand for dissolved oxygen. When you use a pump you are pumping in oxygen which dissolves partially into the water from surface agitation. Since you start with significantly more oxygen than co2 you are basically instantly reducing your oxygen to co2 ratio until you reach the point where atmospheric co2 is dissolving into the water as fast as the oxygen being pumped into the barrels is since your pump is on top of the barrel and co2 is a heavier molecule meaning it is resting closer to the floor. If I were you I would either work to create a convection current in the room, place the pumps on the floor, or get rid of the pumps entirely, and put under water circulation systems like wave makers designed to create surface agitation inside of the water since co2 dissolves 200x more freely than oxygen does forming carbonic acid. Additionally, adding baking soda increases the PH too severely. I would wait to add the baking soda until later in the test as all plant life grows more quickly in a lower PH/softer water environment, and I would even consider adding tannins to the water via wood or leaves to provide readily available nutrient supplies for the algae to take off with.
I had thought the same about placing the airpump intakes near the floor. Good catch!
Wow, very well done! Fascinating. Thank you for your efforts in giving the world this experiment and experience!
Cheers from Texas!
Biology student here. Fun fact: civilization would be fine as far as oxygen goes even if all green plants on Earth were destroyed (because the ocean produces a large percentage of our oxygen). The problem would be that the food chain would deteriorate so we wouldn't have meat (because carnivores and omnivores eat herbivores who eat plants)
I’m pretty sure even without the oxygen producing ocean life, humanity would have enough oxygen for billions of us to survive thousands of years. Even with the massive amount of fossil fuels we’ve used, creating 2,400 Gigatons of CO2, that only raised CO2 levels from .02% to .04%.
Given that the O2 levels are more than 20%, and the average human needs about 1 ton of oxygen per year - all humans on earth use 8 Gigatons/year. The total amount of oxygen in the atmosphere is about 2.6 Petatons (10^15, or million billion tons), so thats at least 325,000 years of 8 billion humans. After half of that, it’ll start becoming harder generation after generation to get enough oxygen and people will live closer to sea levels and it’ll become harder to reproduce, reducing the population needed to support, and causing natural selection to support humans that need less oxygen (becoming shorter, decreasing metabolic speed, etc). but that’s enough time to figure out how to get more oxygen
@@ArtyomiThat's assuming humans are the only oxygen breathing organism on earth which is an interesting assumption.
@@cyan_oxy6734humans are the only organism that I would go to a feuneral for
@@cyan_oxy6734 "an interesting assumption" -- not an assumption! We'll be eating the rest!
Not a very good biology student. The O2 produced from the ocean comes from the plants in the ocean. If you _meant_ all the LAND based plants, then sure. As for the food chain, it'd make little difference to humans, as we could just farm the oceans exclusively.
Try this in the sun. Your lights are not nearly strong enough to get the plants growing and producing oxygen.
maybe he could use some lights to just throw only the amount of wavelength of light that plants need. idk if i'm mistaken, but probably somewhere between the red colors
@@LeftSoulzor just some grow lights….
@@LeftSoulz its verry difficult to recreate sunlight inside. One reason is the combination of wavelengths, another is simply the immense power output needed.
The sun provides every sq.meter with around 1300W of power. Most indoor led lights simply output around 5 to max 40W (old light bulbs) maby max.80W.
That is a drastic contrast to the 1.3kW from the sun.
@@lucaburkhardt2592 well i can see this problem in the proposed situation, where an energy failure could break this system.
that makes the whole using it in space thing pointless though
The next part should include growing hemp in the algae water as the hemp roots will use the extra nutrients in the water and the hemp leaves will grow very fast while providing extra oxygen and a product that can be fed to rabbits who will provide meat and manure which can fertilize all the plants. You really need a complete system for life on Mars.
This guy doesn't half ass. He has whole assed this experiment and I'm all for it and eagerly awaiting the next part!
Except he didn’t do much research to begin with
He's a half assed scientist but he puts his whole ass into it.
So there's been a confusion here from the beginning. The post was about how many plants were needed to meet your oxygen needs, right? But you're measuring CO2 absorption. Those aren't the same thing, right? Maybe 6-8 snake plants are sufficient to supply your oxygen needs, if you have a CO2 scrubber.
About 10 minutes in and I started thinking theres no way that little light is enough to create the carbon chains required here. I would love to know how much water you needed in total, I imagine you needed a ton. Would be expensive to get into orbit, I imagine that is part of the reason why we are trying to find it in space like on the moon.
I noticed the light issue, too. If you get enough light in this small room it will overheat long before you suffocate.
My childhood question wasn’t ever “how many plants do I need to breathe on mars” it was always if you could stick plants into a diving tank so people could breathe forever underwater
Rebreather diving is kinda like that though it just filters out co2 and not turn it back to o2. But you can carry like a few days of o2 in a tank when rebreather diving so it's fine.
Plants don't produce oxygen
They scrub CO2
Oxygen is produced by the ocean
Something to do with the salt in the water not exactly sure how it works
i can confirm that humans can't breathe water, so no you cant do this
What a smart kid.
The ocean supplies most oxygen for humans not plants, there is way more ocean than plants which mostly supply animals and insects especially those in forests which as we know are being chopped down for humans to grow vegetables and livestock hence animal extinction, Every drop of ocean water has millions of diatoms which create oxygen when diatoms die they become fertiliser for forests over millions of years check out, documentary ONE STRANGE ROCK
Thank you for revealing you already had that set! So often UA-camrs have some really elaborate set up for a one-off video and you wonder how the hell they financed and or justified it.
Seeing how intricately decorated your set was, it makes so much more sense now. Thanks again.
As someone who lives in cleveland, I confirm. 1:43