Years ago I met an Eheim rep and talked about the whole concept of fast or slow filtration. The whole gallons per hour concept was just becoming a thing with filters coming on the market. He told me that the speed of the water through the filter wasn't the most important consideration, it was the contact time with the biological media. The longer the contact time the "dirty water" had with the biological media, the better and more thorough the filtration process could be. Thus the early design of the Classic canister filter had no trays or compartments, all the water had to pass through all the media, there was no potential bypass. So agreeing "gallons per hour" is not everything about a good aquarium filter.
Yea, depends very much on what you mean by "filter". Our aquarium filters are up to 3 filters in one: biological filter, mechanical filter, chemical filter. Using one metric to evaluate all three doesn't really make sense. Notice you don't see "gph" on sponge filters. Sponge filters are almost exclusively bio, and flow doesn't really matter (within reason). You DO see gph on canisters, where a huge function is mechanical filtration and flow matters.
Interesting. My latest generation Eheim canister filter has bio mode where I can take the flow rate to be really low at night and then during the day when I use my co2 I have the flow automatically increase. Seems to work well so far. They know how to make a good filter :)
I AGREE ZAZO THAT AQUARIUM FILTERS FLOW RATE NEEDS DEBUNKING. YOUR OBSERVATION OF YOUR OUT DOOR POND REDUCED FLOW RATE IS SPOT ON THE BALANCE OF MICROBS VS GOOD BACTERIA HAS AN EFFECT ON WATER QUALITY, WHEN AMONIA,NITRATES, BALANCED NO FILTRATION IS NEEDED.
Exactly! The first canister filters were also designed in concept of the pool filter. Small pool filters originally relied on pleated cartridges, then they moved to sand media. The water flowed through the top and exited from below.
I think you have an interesting hypothesis. The only thing that I would add to this is that testing is only most efficient against a bare bottom tank. When we get all the surface areas of substrate, hardscape, plants for planted tanks, etc. That adds so much surface area for bacteria in areas that likely have that slower flow, so it becomes harder to determine whether or not it is purely the flow and the media within the filter.
Very good point, and type of substrate, height of the tanks, tank width all play a role in how that flow is dispersed internally. In the filter itself is one issue (baffles might fix) while the tank itself might require higher or lower flow depending on a lot of variables.
To augment your point regarding flow rate, Diana Waldstad discusses the allied topic of plant interaction with the water column in her book "Ecology of the Planted Aquarium". There she indicates that most plants are able to more effectively extract substances from slower moving water. Keep producing interesting and educational videos!
Flow rate is usually not good or bad for bio filtration (unless you're not getting oxygen in there) because diffusion is a thing (ions in water aren't all in one place like the rag). Most of the time people have more surface area than they need too. So bio is rarely a problem regardless. So what's left is mechanical, if that matters to you, where flow rate matters and gph is a useful metric.
I can relate that theory back to thermal dynamics. If you have a water pump with too high of a GPM then the radiators or baseboard don't have enough time to pick the heat up out of the water before it flows by so you get less heat in the room.
Spot on Zenzo! I learned that back in the 60's. Nitrifying bacteria needs contact time to process the ammonia & nitrite so a slow flow is essential. Back then your gravel and decor housed the bacteria and the HOB's were for water polishing which was usually based on the fishes needs plus tank gallon size. Our HOB's were siphon fed with the motor outside above the filter box. Little fry usually survived as they would swim above the floss. UGF's worked best for beneficial bacteria growth and processing as the oxygenated water flowed slowly through the gravel. If properly maintained that so called one inch of fish per gallon rule could easily be broken. In my barren breeding & grow out tanks the water flow was slow operating box filters. I never cleaned the glass when I cleaned the filters as the bacteria would be every where. Had no problems operating my fish room that way for many decades, still do.
Agreed. More interest in amount of media it can hold and still have enough oomph to push water through all the sponges and media. Don't want an under powered unit if you are packing media and sponges and then there is barely a trickle coming out of it.
Interesting. Not entirely on board with the idea that a slower flow will allow BB to work better. The BB is going to grab the nutrients it needs to survive and whether it’s grabbing it from a fast or a slow moving nutrient supply, the net nitrification result will be the same. Reminds me of those conveyor belt sushi restaurants. No matter how fast that belt is moving and that sushi is flying by, I’m going to still grab all the sushi I want (usually more than I should 🤣🤣🤣).
Your theory makes complete sense. I'm a return fish keeper. Was in to about 20 years ago and just started back into it again at the age of 60. There is so much easier access to the knowledge of the hobby. Thanks for sharing yours.
Great video Zenzo. I was wondering about flow rate lately on my fluval 407 canister filter. It's on a 60 gallon and to me seems to have a powerful output. I've packed most of the baskets with filter pads. Kept the ceramic pellets and bio balls for beneficial bacteria growth. Didn't seem to phase the flow. So now I've put a filter sponge over it and that has done the trick. Nice flow now. Fish loving tank.
I agree with what you're saying. I would like to see more HOB that has deeper media storing area and adjust the angle of the water going back into the tank.
I used to look at litres per hour. Not so much now. I focus primarily on as much surface area for the beneficial bacteria to grow. Most of the filters are far too powerful for my bettas anyway so I used sponge filters for them. My community tank has 2 canister filters with multiple media. I use loads of media so I can alternate cleaning of the Sponges, always use floss, coarse, fine sponges then media like ceramic rings and bio balls. Geat informative video Zenzo thank you 😊👍
The best part of the video is "Better Attributes in a filter" it usually comes down to what the live stock, example Bettas like low flow so dial it down, shrimp tank no mechanical parts and slow slow, high energy river stream fish given them the flow that they like in the nature... Great video as always 🤩👌🏻
Great video, Zenzo! I liken this to Nurburgring lap times. Many companies tout the lap record, but I can’t help but feel that it only proves the car is fast in that environment. Most of us don’t drive the Nurburgring on a daily basis. Not that I’d mind if I had to. 😂
Great video! So you're correct about the time it takes bacteria to digest. That being said, I think that GPH is the easiest/best way to measure and market that information.
I completely agree with you. I put a sponge filter with very little water movement in my new 10 gallon tank and it was cycled in a week. I put 2 tidal 75 in my new 55 gallon with a lot of water movement/ flow rate and it’s been almost a month without it been completely cycled!
I don't think the flow rates in your average filter gets anywhere near to the level required to inhibit bacterial function. If it did, we'd know about it soon enough because the fish would be reacting to the build up of ammonia. The most amount of scientific research into nitrification is with regards to water treatment plants - sewerage plants. The water flow rates there is way higher than you'll get from a domestic filter. Another thing, although a filter may say 300 gallons per hour, the water molecules and everything dissolved in it will flow at different rates as it passes through the media. As the water contacts any surface it slows down, it has to wrap around the bioball or whatever media you're using and this is going to slow the water at the locality of the media. TLDR - if there's no build up of ammonia in an aquarium, the filter is working.
While I don’t disagree with your take on flow rates, I don’t think his point was that high flow filter didn’t work per se. but rather that he didn’t think high flow = most effective or that high flow was the most important factor. Yes I do acknowledge that he inferred that high flow may actually do more harm than good. Having said all that I’m not sure his take on things was 100% sound either.
Bacteria (different types) grow bases on flow rates. The QTY of bacteria is why flow isn't an issue. Rate aside. Because of the amount of surface in the aquarium, generally, ammonia won't ever be the main issue.
I think it also helps determine what filter you need for certain fish, some like very high flow and some like no flow at all and I think measuring the strength of the pump in how many gallons per hour it can move is a good way to determine how fast it is. You can almost always slow down flow but you can’t always speed it up unless your filter has that strength. If you want a smaller filter for space or aesthetic reasons it’s better to have the option of a stronger filter to compare to others of the same size. Another thing people don’t always realize is usually they come up with that number when there’s no media in the filter at all, so every time you add something into the filter it’s gonna get a little slower. I’ve been switching to HOBs recently since my tanks are more spread out now and can’t all run on the same air pump and I really like how easy they are to access and customize, although I hate that the water can be too easily directed to the wrong exit of the filter. There’s just too many paths for the water to go and I feel like it isn’t going through the media as well as it would in a canister where the water has no other place to go since it’s a fully closed filter. I do like that HOBs are a bit easier to clean than a sponge and don’t cloud the water when putting it back in, and I don’t have to clip back on all the pieces of a sponge filter.
Can you make a video about under gravel filters? Everyone used them back in the 70's when I was a kid and had my first tank. Now it seems like they've gone out of fashion.
I've only been into this glass box scene for a couple of years and was initially sold a 10g tank with a HOB that required filter cartridges which were to be replaced monthly. The more I learned, the less I stuck with the concept of these replaceable filters. I first started using my own filter floss in tandem with carbon impregnated sheets cut to the size of the original filters. After about a year of that I stopped using the carbon filters and just used a piece of sponge. The tank worked fine without all the original rigmarole. Eventually it occurred to me that the bacteria in the filter were probably being subjected to what happens when you give a drink to a dog from a garden hose at full blast, except that it was probably more like watering the dog with a FIRE HOSE!!!! LOL. So, I basically switched over to air driven sponge filters where the flow is nice and slow and gentle. My water is crystal clear, there's never any smell and my parameters are always within a good range. Truth is, I probably don't even need the sponge filters as I've also since learned that beneficial bacteria are on every surface of every rock, plant, substrate and even the walls of the tank, doing their job munching Ammonia and nitrites anyway. The movements of the fish and shrimp themselves are probably enough to cause enough surface agitation to enact the gas exchange between the tank water and the atmosphere also making the sponge air filter surface agitation unnecessary. But I'll keep them for now, the bubbles are soothing!
Thank you for sharing this video and the idea of flow being the holly grail has never stuck to me. I'm a believer that the beneficial bacteria are the key and my goal is to try and keep a balance between them and fish waste. Also liked the way you explained how it should work on a filter, independent of the brand.
I stopped worrying about GPH ages ago. It is a number meant to attract people, who put trust in products before they use them. I mean if you are new, often you don't know where to look, so you trust the ads. I use Sponge filters with an HOB so two types of filters but I can make the HOB either a mechanical filtration with bacterial filtration, or it can be used with strictly ceramic media or as you showed, sponges. I like current in a tank so the combination of sponge filters and an HOB is an inexpensive way to get this. I think Pond Guru got me turned into this a few years ago. Thanks Zenzo, good information!!
What are your thoughts on flow rates and filters? If you enjoyed this video, here is another video that you may enjoy: ua-cam.com/video/hbjdm21twy4/v-deo.html Link to fish foods, plants, and aquarium supplies www.aquariumcoop.com Follow me on Instagram: instagram.com/Tazawa_Tanks Tazawa Tanks Merchandise: shop.spreadshirt.com/tazawa-tanks/all
A slow filter is most likely the Best water purification possible, Reverse Osmosis units would be the simplest example, but as you said in this video, beneficial bacteria work Best with long exposure times.
I definitely like this video,because I believe the slower flow rate definitely improves the aquarium by letting the bacteria do what it was made for.very insightful sir.
Another consideration with regards to flow rate through media is that if you have a very slow flow rate and a very large amount of media by the time the water has travelled through the media the aerobic bacteria would have used a large amount of the oxygen contained within that water giving you the potential to develop anaerobic bacteria farther along within the media therefore dealing with nitrate aswell as ammonia and nitrite. Provided the water is oxygenated on its return to the aquarium would vastly improve the health of the aquarium and inhabitants.
Interesting video! I was going to listen to on way to LFS but nine plus inches of snow falling today.Jeff Miotke was in today giving an scaping demo,got to give the man credit besides the owner and store staff only four of us diehards made it. The man still did the from nothing to scaped tank and Oase bought lunch. After a very slow ride home I’m watching now.
Totally agree that GPH is not something to fixate on when choosing a filter. Media volume, inflow/outflow design and safety, even noise are probably more important things to consider.
I think you are correct. I use a diy top of the tank filter for almost 10yrs. Powerhead to top of tank box. Slows the flow compared to the aquclear 110 Bare bottom 4goldfish 60g tank.more sponges and quilt batting makes a gentler flow. Crystal clear water too.WKLY water changes 50%.I use a Co-OP ceramic media bag too!
I mainly pay attention to the gallons per hour thing now because I want to know how strong the flow will be in the aquarium. Currently, I have aquaclear filter rated for a larger tank than the one I have so the flow is pretty strong and I don't think my neons like it so much. For next time, I might get a weaker filter or just go with a sponge filter. Though I don't like how much noise those air pumps make.
I use sponge filters for beneficial bacteria and HOB to polish water at the same time for this same reason. also I prefer HOBs that have the flow adjustment for this very reason as well.
I totally agree. In nature when a creek has a rain running through and flow is increased the water becomes turbid and you can't see through it anymore. Water needs dwell time in contact with the media, and the surface area needs to be large enough to handle the fish load. Blasting the water through is putting the filter in cleaning mode, not filter mode.
I just have one big air pump and all my tanks on air filters, the pump is 35L/min, around 550 gallons per hour, running 11 tanks and could probably do a lot more. Very efficient and cheap to run! I like to make bottle filters with crushed lava rock and put a sponge on the bottom, and also run normal sponge filters on all tanks
I like knowing flow rates. Most fish I like to keep do better not being blown around the tank so I like lower flow and I only rely on hob if I need extra mechanical filtration. Flow is an important consideration with sumps especially so you know you’re using a well designed system as waters leaving the tank and being returned. It’s simply a metric to work with and not the whole picture.
It's actually funny when I think about when I first started keeping fish which was only two years ago I was super concerned about the water being super clean and running my tidal on the highest setting. Nowadays I pretty much have it tuned to about 20 to 25 percent flow and just vacuuming up whatever is left every week. I feel like I had to come to the realization that the filter would never get everything and my fish would be happier without all that flow, unless I was keeping hillstream loaches or something like that.
I've recently came back to the hobby and started on planted tanks. I've seen people saying "More flow better success". I never listen and you put a seal on my 40g breeder. Sicce Whale 500 flowing like an Aquaclear 50 and all of my plants look great and well the fish thriving....
The following theoretical situation isn’t proven nor real but could be used as an example with the logic you provided. One aquarium filter recycling the tank 10 times per hr and requires a certain part of water to be recycled twice to fully remove the ammonia and impurities in the water while another requires that same part of water to only be cycled once through the system to remove ammonia and impurities through the water but only recycles the tank 5 times per hour. Both of the filters will remove all the ammonia and impurities from the water just as quickly. The best product is one that requires only one cycle through the filter while recycling the tank the most per hour. Accomplishing this is simple, by using a wider path where the filter media is, the water will travel more slowly through the media allowing all the impurities to be removed in one cycle while having a high flow rate. The flow rate of water and the speed of water movement are not the same and creating a wider path reduces the speed of the water movement but not the flow rate. Once again, this is theoretical, not real.
As far as I've noticed, sponges do the trick just fine for bio. So, I've taken to HOBs and internal canisters for mechanical and chemical filtration. Haven't had any issues since.
Thanks Zen! residence Time‘s is what I call it. The amount of time it takes for the chemical reactions to take place. That’s what you want for biological filtration and general chemical filtration. Mechanical is where you want all the turnover very good video to break it down.
I do try to shoot for that 10 times per hour for water clarity though, the more you pass through physical filtration the more particles get picked up , most beneficial bacteria is on substrate and surfaces in the aquarium. The numbers filters give are with no media and no head distance
It’s interesting because I think that mechanical filtration primarily collects debris into its media and as that media collects, it either stays there until it is removed for cleaning or is consumed, partially or completely, by the bacteria. The gallons passing through shouldn’t be the primary calculation of filtration because the media does most of the work collecting it. If the media wouldn’t be there than some of it could cling to the walls of the filter or the pipes but for the most part everything moves with the water. The rate of flow could be used to see how full the filter is or if the motor/pump is struggling.
Interesting. Makes sense actually. I've always bought a filter with a flow rate one step higher than necessary for the size of the aquarium and I probably still will do that, but I may just slow the flow rate down and see what happens.
From experience I agree with this theory, I’ve found that it’s better to have a weaker flow with as much filter media as possible rather than strong pump and less media. The only advantage with the high flow rate is it keeps detritus from building up in dead spots, however you can supplement with a power head to move water around and keep particles suspended till they get sucked in the filter.
I totally understand what you are saying but I think there is a key point you're missing out on. As an example, my 75G running probably half of those filters you showed over time. I had a 55G and took everything from that tank and went to a 75G. Guess what..... The filter flat out didn't fit the rim. So then I had to go buy the one that had the spacing for the larger rim. Flowrate went up and I had so many issues with the sand substrate being blown away from the front of the tank because of how intense the flow is. I generally prefer to run two 75g "flowrate" filters on my tank. The tank isn't set up due to some construction but ran for years with two of the tidal 75s on either half of the tank. I absolutely still had issues with the substrate moving, but the key factor being that the tidal has by far one of the best pump/impeller designs and the best flow control system of any filter available. What I did to "fix" issues like the above was to side mount the filter and force the water to go the length of the aquarium. Think about it. It's a typhoon of flow, but we are told it should run 12-24" instead of the 36-48" on the length of the tank. More flow helps with more oxygen in the water, some fish demand that oxygenation. I focus my flow requirements on what the FISH NEED. The GPH is just a stat on the box because it's one way for the design engineer to state it's intended use case. Imagine a filter where the pump you used could be controlled by the user, or better yet, where the pump itself could be added after the fact by the user easily and was high quality. The HOB itself allows the pump to be adjusted, but the box supports a low, medium, high flow filter in any use case. You buy the box, you buy whatever "flow" you need, but you gain room for media and for sponges instead of having to be forced into A size by the tank. That's why so many years ago all of those videos took off of people making their own HoB or modding HoB just to function better. Yeah, there is absolutely a disconnect between the designer of some of these filters and the managers of those filters (their goals) in comparison to day to day use by a hobbyist. Furthermore, as someone who can design things for a living, and who has been in the hobby long enough to know that the majority of the filters just don't work well, it's tough to see some of those design choices just to force replacement parts or to force replacing of low quality media. Would be cool to see you do a video talk with Pondguru on filters. That guy has a massive amount of knowledge and some great videos.
I use the litre per hour to get a rough estimation about how much flow the filter can create in the tank. Not how effective it is. It is a pump after all. All pumps are labled with litre per hour values. Not just aquarium pumps.
The wildest thing about those gallons/hour stats on filters is that they measure them based on the rate when the filter is empty, not when it is full of media…so it’s an extra useless stat since nobody is going to run their filter without media in it.
I have AquaClear on my salts and tidal on my freshwater like both but tidal you can hang you heater I like that seems to spread Heat more evenly cause it next to intake tube both you can adjust flow rate
I am interested to see how your tests come out but right now I am not so sure the the speed of the water going though the media is going to show much. And not sure how exactly you would test this. My thought is the tank and everything in the tank is what houses the BB, yes it’s in the filters but I look at the filters as more mechanical polishing the water a place to put gfo and carbon
Interesting because I have been doing a little research into this , especially the anoxic filtration, which is not aerobic like the oxygenated water needed for our bacteria that converts ammonia and nitrites into nitrates but a very low flow ( under .05ppm oxygen ) and it is not anaerobic which is 0 oxygen often found in deep sand beds tanks . It is a very low flow low oxygen level that houses a beneficial bacteria that actually uses oxygen from the nitrates. The bacteria in these low flow zones consumes the oxygen from the nitrates (no3) in the water. Takes those 3 parts of oxygen leaving nitrogen that then gasses off harmlessly . It’s a bit sciencey for me but Dr Kevin Novak’s videos explains how this works a lot better than I ever could . That is how he runs all of his nitrate free tanks. The slower the flow and lower oxygen levels creates a totally different bacteria that actually consumes nitrates. Specifically his plenums or undergravel filters are known best for this process. It’s technically different to what you were explaining but it definitely is a interesting take on how bacteria works and how different flow levels and oxygen levels work in the aquarium 👍🏼 Edit - I do think the housing of the biological filtration is one of the most important rolls in our aquarium as well as The mechanical I guess , which is probably more for oxygenation and keeping poop and food etc particles out of the water. Interesting to see a different video with a different view and take on the filtration , Thankyou 👍🏼
I use a single tidal 55 on my bigger tanks with a deep sand substrate with lots of plants. I keep my lights on 10 hours a day and that seems to do the trick. I use a pre filter sponge on both from aquarium co-op of course, with more sponge and poly fill in the basket. In my 10 gallon tanks deep substrate and a single sponge filter with plants and lights the same as the other tanks. They all look good and waters tests just fine. I think some good filtration happens in that substrate. But I'm in agreement with the gph. If you run all your water through that filter at least once an hour you should be all right. There's tanks out there right now that have no filtration at all and doing fine. Just saying.
👍😎 Same kinda thinking as Jason (Pirme Time) who is way more knowledgeable than most of us when it comes to aquariums. He rinse’s his media in tap water because the chlorine doesn’t have enough time to harm enough bacteria to be considered with. Never thought of that when it comes to filter’s. Interesting. 🖖
I think it was LRB, showing off a filter that he wasnt sure if it even worked it had such large plant growth. But i packed my hang on back with plants to slow the flow as well
I'm more about total media surface area and less about flow rates. I'll purchase my filter, or adjust my flow rate, for the particular aquarium and fish.
I have a 10G with shrimp so I have a little HOB with sponge, filter floss, and crushed coral. It slows the flow. On the other hand I have a 40G with 2(1 year old) turtles, 2 albino plecos, 2 red blood parrots, some Cory cats(5-6), and a handful of guppies and zebra danios. On that I’m running a 110 fluval aqua clear with sponge, bio balls, and some crush coral plus another little “turtle” filter in the water and a sponge filter. I want a good amount of water flow to keep the water clean and clear. The waste from the turtles and plecos is pretty good size so need lots of flow. The little inner filter is set on a timer so at night it turns off and I usually put the big 110 fluval on low to give the fish calmer water at night. I do weekly water changes and nitrates stay below 40. No plants since the turtles and plecos and Corys uproot anything I plant :( next year once I move I’ll be getting a bigger tank for the turtles.
I totally agree with you. But how about moving bed filter ? The flow rate need to be strong in order to cause the media to move. Does that really create benefital bacteria?
With a moving bed filter, the flow is actually not that strong (water in and out), and the media is submerged in the water it’s “treating”, so theoretically in contact longer. Great question/point though!
I agree with you with the exception being if someone have deep substrate, driftwood and plenty of surface area to harvest bacteria, then it won’t matter much. The amount of media you can store in your filter would probably make more of a difference if the nitrogen cycle is your main concern. If I’m spending all that money for a filter I am definitely concerned with gallons per hour because the only real advantage of having a canister or HOB versus a sponge filter would be water polishing. I could just put a bunch of lava rock inside the tank if I want to harvest bacteria.
Totally agree with surface area with sand bed depth and rock. Drift wood is spectacular in that it not only has the external surface area, but with its absorption of water, it has both aerobic and anaerobic properties for full cycling. Thus the high flow rate is important for continuous water movement over the whole tank, creating current for fish to swim against, and suspending solids for water polishing.
Haha what I did for my first tank. I did all this research on substrate that produced the most bacteria and give places to hide to those bacteria. Totally went all out with a black volcanic rock substrate tank. With red lava rock used for grills as decorations. Note: I do still run an air filter just in case something dies. My tank is very overstocked.
Flow rate tells you more about how long it takes the filter to slow down than anything else, sooner or later the rate will even out no matter how powerful the filter is.
Eheim has been sizing their filters this way for decades; flow designed to maximize the nitrogen cycle, while still creating enough flow to mechanically filter the water. Remember trickle filters? Slow moving, highly oxygenated water that swallowed all the ammonia and nitrites. Wrongfully called nitrate factories because people didn’t clean the mechanical filters enough. Keep your bb clean by cleaning the mechanical media often. Some of us use two filters for this very reason; a slow one for bio and a quicker one for mechanical. The slow one also clogs less… which is perfect. An example of apples to apples: two sponge filters in the same tank. One is very coarse, doesn’t trap much, and has the airpump set on low. The other is fine, catches everything, and has the airpump set on high. One for bio and one for mechanical. Clean the the mech. one frequently. Theil (Thiel?) wrote some great books/articles on this in the 80s as did Moe.
i go if you have 100L tank take 200L filter and slow it down works for me for now last year i didnt clean filter becouse it is nothing to clean having sponge filter on inlet and everything is stucking to foam
The upside of the gallons per hour is the current it puts in the tank. Many fish live in very active rivers and we don't do a very good job replicating that current in the hobby. Wave makers for example are generally used in salt water tanks. The higher water flow filters do a better job replicating this as well as how heavy they oxygenate the water. While it isn't the be all end all stat for a filter I still think it is very important
If you put as much media as you possibly can in to a to a tight bag and stick it in your filter/sump the water will flow really slowly through the center of the bag great for beneficial bacteria
I use sponge filters and hang on backs. Sponge filters for biological filtration and hang on backs for mechanical. I don’t like using just sponge filters because they don’t do a good job of mechanical filtration in my experience. I think some large particles get trapped in the filter of the hang on backs. There, the bacteria can break it down.
I think brand, flow rate, the amount of filter media (size) are the only ways to evaluate filters that aren’t sponge filters. Even sponge filters are compared by size. I firmly believe buying a filter capable of doing 10x your water volume is a good metric bc the manufacturers measure GPH without any media. When we stuff every possible nook and cranny of our filters with media, we can effectively halve that flow rate.
Other things to consider: available parts, power consumption, self-priming or manual priming, capacity to add more media, ability to modify, ability to alter flow rate, easy of cleaning, etc.
I do believe flowrate is a factor in filtration. But not as much as brands make it appear in their marketing. First of all, all the flowrates need to be cut in half anyway cause they are measured without media in the filter. And depending on the type of media it slows down significantly. So im with you on that. The other side I dont think the aerobic bacteria have trouble with higher flowrates. I mean its how moving bed filters work. There is constant chaotic movement and the filters break down ammonia without issues. I believe that what you describe is more a factor with Anaerobic bacteria. They need slow moving water with low levels of oxygen to break down nitrate to nitrogen. And if you got a massive filter with high flowrates with media that lets water pass really fast. You never get a full nitrogen cycle.
I've talked about this with some old timers, and they say the faster, the better to ram water through my cannister filters, even for biological processes, I on the other hand think to slow it down would help with biological processes in being in contact longer with my bio material would be a benefit. They all disagree! Only thing I can say about that is maybe the split second or so gained by slowing the flow doesn't help. I'm not a chemist!
I have never payed any attention to filtration flow rate. It is the tank that will tell me what it needs, the flow rate of my filtration all gets worked out during the time I am balancing the tank out and yes it does take time. My flow rates will change as needed through this process and eventually I will end up with the perfect flow rate that is good for the fish, good for the plants and good for filtration. Each tank is different, in reality there is no one size fits all just some general guidelines. Your tank will tell you what you need, learn how to recognize what your tank is telling you.
if that is the case slow your filter to 1 gph and see what happens. There is a happy medium between flowrate and a good environment. This will differ in all cases because no two aquaeiums will ever be exacrlty alike. The more you process water through a filter media the more solid waste it will remove quicker. The more water flowing means even heat distribution throughout the tank. if you dont have sufficient bacteria to handle the bio-load of the tank putting water through a filter will not remove ammonia. I use cansiters and sponge filters in my tanks so I get the best of both worlds. Sponge filters work well, they strain the particulate matter while giving bacteria a place to colonize. Canister filters do the same thing on a vastly ;larger scale and they agitate the water better for more 02 exchange at the surface. Warm water does not hold as much O2 as cold water does so you need even more agitation in a warmwater tank depending on the amount of fish you have vs surface area. Sponge filters are great for jump starting new tanks as well. I fishless cycle my tanks with straight ammonia from day one so I never worry about bio load when my fishless cycle can deplete 2-3 ppm of ammonia within 24 hours i can dump a ton of fish in a tank and never have an issue b ut doing it this way can take 3-5 weeks sometimes. Using a s cycled sponge speeds it up a bit but not by that much in my expirience. Nature takes time and when you mess with it you get messed up results. Sumps are great filters and have massive contact to water flow time due to the fact they are just gigantic canister filters . At the end of the day will a small canister filter meant for a 55 gallon tank work on a 100 gallon tank, sure it will. Would I use that if I had to , sure, Would one with a better flow rate and more media be better, YES. How much better is the question but at the end of the day who GAF when the price of the next size up is 30-50 more dollars. In the grand scheme of things when you are dealing with hundreds of dollars of fish are you willing to skimp on filtration to begin with? The whole discussion ends in a meaningless waste of time
Great video. There was a time when under-gravel filters were king. This whole GPH myth is just that, a myth. It's something that was invented to market the very first powered filters over the use of under-gravel filters. The most important part of filtering water is biological, where a low flow rate is key, everything else is secondary. Fish husbandry went hand in hand with UGF by siphoning any wastes in your tank, thus acting as a mechanical filter in conjunction with the biological filtration from the UGF. The problem with today's filters is they try to be all in one, making the fishkeeper a lazy fishkeeper and putting husbandry on the wayside. My preferred tank filtration is still UGF, but now with my DIY canister filter heavily outfitted with sponges, EHEIM Substrat Pro, and my DIY Chemipure. I also use a water flow meter on my canisters to tell me when it's time to clean my sponges. Whatever filtration one chooses, fish husbandry should never be a byproduct of your filtration.
I hate to say it but we're overthinking this. Water moving fast or slow doesn't change the ability for biological filtration to take place, at least not in a way that's meaningful to an aquarist. We did experiments like this in college but rather than commercial filters we used lava rocks and a sump. The first stage was simple over flow with a small return pump. We progressed in stages until there was a huge pump in the tank and the sump and it was a whirlpool in both. It wasn't until that point that there was a meaningfull difference but that is far about flows the hobby would have. Our hypothesis was that the flow was so strong only aerobic filtration was occurring. However, it was never tested
I am by no means an expert but I think there is a lot of fashion in this hobby that is accepted as fact: you must have 10x turn over flow filters, canisters are the be all and end all of filtration, you must use the most PPI media available to science and everything else is useless. My experience and therefore my opinion is all of this is not true and is more fashion than fact.
I'm wondering if it'd be feasible to use two filters. Here's my logic. Use one filter that is big enough to use slow flow to biologically filter the water, and a second, maybe smaller with a higher flow rate to polish the water and suck up any solid waste. I'm thinking that if the bio filter is slow enough, it's not going to suck up as much solid matter, and therefore not get clogged/cleaned as fast,. And then you just have to clean the smaller particulate filter that will suck up mass quantities, and polish the water. The issue I have with it is that you have two things plugged into power. For my personal use, I'm thinking of building a custom sump where I only have to really worry about one pump, and cleaning the particulate filter. For somebody that doesn't have the space to put a sump for example, would two separate filters for different uses be feasible? I'm talking about power, space, cost?
Years ago I met an Eheim rep and talked about the whole concept of fast or slow filtration. The whole gallons per hour concept was just becoming a thing with filters coming on the market. He told me that the speed of the water through the filter wasn't the most important consideration, it was the contact time with the biological media. The longer the contact time the "dirty water" had with the biological media, the better and more thorough the filtration process could be. Thus the early design of the Classic canister filter had no trays or compartments, all the water had to pass through all the media, there was no potential bypass. So agreeing "gallons per hour" is not everything about a good aquarium filter.
Yea, depends very much on what you mean by "filter". Our aquarium filters are up to 3 filters in one: biological filter, mechanical filter, chemical filter. Using one metric to evaluate all three doesn't really make sense. Notice you don't see "gph" on sponge filters. Sponge filters are almost exclusively bio, and flow doesn't really matter (within reason). You DO see gph on canisters, where a huge function is mechanical filtration and flow matters.
Interesting. My latest generation Eheim canister filter has bio mode where I can take the flow rate to be really low at night and then during the day when I use my co2 I have the flow automatically increase. Seems to work well so far. They know how to make a good filter :)
I AGREE ZAZO THAT AQUARIUM FILTERS FLOW RATE NEEDS DEBUNKING. YOUR OBSERVATION OF YOUR OUT DOOR POND REDUCED FLOW RATE IS SPOT ON
THE BALANCE OF MICROBS VS GOOD BACTERIA HAS AN EFFECT ON WATER QUALITY, WHEN AMONIA,NITRATES, BALANCED NO FILTRATION IS NEEDED.
Exactly! The first canister filters were also designed in concept of the pool filter. Small pool filters originally relied on pleated cartridges, then they moved to sand media. The water flowed through the top and exited from below.
Be mind he was a rep not a scientist.
I think you have an interesting hypothesis. The only thing that I would add to this is that testing is only most efficient against a bare bottom tank. When we get all the surface areas of substrate, hardscape, plants for planted tanks, etc. That adds so much surface area for bacteria in areas that likely have that slower flow, so it becomes harder to determine whether or not it is purely the flow and the media within the filter.
Very good point, and type of substrate, height of the tanks, tank width all play a role in how that flow is dispersed internally. In the filter itself is one issue (baffles might fix) while the tank itself might require higher or lower flow depending on a lot of variables.
To augment your point regarding flow rate, Diana Waldstad discusses the allied topic of plant interaction with the water column in her book "Ecology of the Planted Aquarium". There she indicates that most plants are able to more effectively extract substances from slower moving water. Keep producing interesting and educational videos!
Flow rate is usually not good or bad for bio filtration (unless you're not getting oxygen in there) because diffusion is a thing (ions in water aren't all in one place like the rag). Most of the time people have more surface area than they need too. So bio is rarely a problem regardless.
So what's left is mechanical, if that matters to you, where flow rate matters and gph is a useful metric.
I can relate that theory back to thermal dynamics. If you have a water pump with too high of a GPM then the radiators or baseboard don't have enough time to pick the heat up out of the water before it flows by so you get less heat in the room.
Spot on Zenzo!
I learned that back in the 60's. Nitrifying bacteria needs contact time to process the ammonia & nitrite so a slow flow is essential. Back then your gravel and decor housed the bacteria and the HOB's were for water polishing which was usually based on the fishes needs plus tank gallon size. Our HOB's were siphon fed with the motor outside above the filter box. Little fry usually survived as they would swim above the floss. UGF's worked best for beneficial bacteria growth and processing as the oxygenated water flowed slowly through the gravel. If properly maintained that so called one inch of fish per gallon rule could easily be broken.
In my barren breeding & grow out tanks the water flow was slow operating box filters. I never cleaned the glass when I cleaned the filters as the bacteria would be every where. Had no problems operating my fish room that way for many decades, still do.
Agreed. More interest in amount of media it can hold and still have enough oomph to push water through all the sponges and media. Don't want an under powered unit if you are packing media and sponges and then there is barely a trickle coming out of it.
Interesting. Not entirely on board with the idea that a slower flow will allow BB to work better. The BB is going to grab the nutrients it needs to survive and whether it’s grabbing it from a fast or a slow moving nutrient supply, the net nitrification result will be the same. Reminds me of those conveyor belt sushi restaurants. No matter how fast that belt is moving and that sushi is flying by, I’m going to still grab all the sushi I want (usually more than I should 🤣🤣🤣).
Super excited for the filter data you collect!
Your theory makes complete sense. I'm a return fish keeper. Was in to about 20 years ago and just started back into it again at the age of 60. There is so much easier access to the knowledge of the hobby. Thanks for sharing yours.
Thank you for the deep dive in filtration flow and your thoughts on it.
👍❤👍
Great video Zenzo. I was wondering about flow rate lately on my fluval 407 canister filter. It's on a 60 gallon and to me seems to have a powerful output. I've packed most of the baskets with filter pads. Kept the ceramic pellets and bio balls for beneficial bacteria growth. Didn't seem to phase the flow. So now I've put a filter sponge over it and that has done the trick. Nice flow now. Fish loving tank.
I agree with what you're saying. I would like to see more HOB that has deeper media storing area and adjust the angle of the water going back into the tank.
Bro you should rep the cut offs more often haha cause you are STACKED! Keep up the great work man, your tanks and information are amazing!
I used to look at litres per hour. Not so much now. I focus primarily on as much surface area for the beneficial bacteria to grow. Most of the filters are far too powerful for my bettas anyway so I used sponge filters for them. My community tank has 2 canister filters with multiple media. I use loads of media so I can alternate cleaning of the Sponges, always use floss, coarse, fine sponges then media like ceramic rings and bio balls. Geat informative video Zenzo thank you 😊👍
The best part of the video is "Better Attributes in a filter" it usually comes down to what the live stock, example Bettas like low flow so dial it down, shrimp tank no mechanical parts and slow slow, high energy river stream fish given them the flow that they like in the nature... Great video as always 🤩👌🏻
Very good insight. Definitely have me thinking! 🤔
Great video, Zenzo! I liken this to Nurburgring lap times. Many companies tout the lap record, but I can’t help but feel that it only proves the car is fast in that environment. Most of us don’t drive the Nurburgring on a daily basis. Not that I’d mind if I had to. 😂
Great video! So you're correct about the time it takes bacteria to digest. That being said, I think that GPH is the easiest/best way to measure and market that information.
Killed it with this video bro and it shows! Haha look at that handheld gimbal goodness 💚
I completely agree with you. I put a sponge filter with very little water movement in my new 10 gallon tank and it was cycled in a week. I put 2 tidal 75 in my new 55 gallon with a lot of water movement/ flow rate and it’s been almost a month without it been completely cycled!
I don't think the flow rates in your average filter gets anywhere near to the level required to inhibit bacterial function. If it did, we'd know about it soon enough because the fish would be reacting to the build up of ammonia.
The most amount of scientific research into nitrification is with regards to water treatment plants - sewerage plants. The water flow rates there is way higher than you'll get from a domestic filter. Another thing, although a filter may say 300 gallons per hour, the water molecules and everything dissolved in it will flow at different rates as it passes through the media. As the water contacts any surface it slows down, it has to wrap around the bioball or whatever media you're using and this is going to slow the water at the locality of the media.
TLDR - if there's no build up of ammonia in an aquarium, the filter is working.
While I don’t disagree with your take on flow rates, I don’t think his point was that high flow filter didn’t work per se. but rather that he didn’t think high flow = most effective or that high flow was the most important factor.
Yes I do acknowledge that he inferred that high flow may actually do more harm than good.
Having said all that I’m not sure his take on things was 100% sound either.
Bacteria (different types) grow bases on flow rates. The QTY of bacteria is why flow isn't an issue. Rate aside. Because of the amount of surface in the aquarium, generally, ammonia won't ever be the main issue.
@@nabokovfan87 Ammonia and Nitrite are the main issues and practically the only issues when it comes to fishkeeping.
I think it also helps determine what filter you need for certain fish, some like very high flow and some like no flow at all and I think measuring the strength of the pump in how many gallons per hour it can move is a good way to determine how fast it is. You can almost always slow down flow but you can’t always speed it up unless your filter has that strength. If you want a smaller filter for space or aesthetic reasons it’s better to have the option of a stronger filter to compare to others of the same size. Another thing people don’t always realize is usually they come up with that number when there’s no media in the filter at all, so every time you add something into the filter it’s gonna get a little slower. I’ve been switching to HOBs recently since my tanks are more spread out now and can’t all run on the same air pump and I really like how easy they are to access and customize, although I hate that the water can be too easily directed to the wrong exit of the filter. There’s just too many paths for the water to go and I feel like it isn’t going through the media as well as it would in a canister where the water has no other place to go since it’s a fully closed filter. I do like that HOBs are a bit easier to clean than a sponge and don’t cloud the water when putting it back in, and I don’t have to clip back on all the pieces of a sponge filter.
Can you make a video about under gravel filters? Everyone used them back in the 70's when I was a kid and had my first tank. Now it seems like they've gone out of fashion.
I've only been into this glass box scene for a couple of years and was initially sold a 10g tank with a HOB that required filter cartridges which were to be replaced monthly. The more I learned, the less I stuck with the concept of these replaceable filters. I first started using my own filter floss in tandem with carbon impregnated sheets cut to the size of the original filters. After about a year of that I stopped using the carbon filters and just used a piece of sponge. The tank worked fine without all the original rigmarole. Eventually it occurred to me that the bacteria in the filter were probably being subjected to what happens when you give a drink to a dog from a garden hose at full blast, except that it was probably more like watering the dog with a FIRE HOSE!!!! LOL. So, I basically switched over to air driven sponge filters where the flow is nice and slow and gentle. My water is crystal clear, there's never any smell and my parameters are always within a good range. Truth is, I probably don't even need the sponge filters as I've also since learned that beneficial bacteria are on every surface of every rock, plant, substrate and even the walls of the tank, doing their job munching Ammonia and nitrites anyway. The movements of the fish and shrimp themselves are probably enough to cause enough surface agitation to enact the gas exchange between the tank water and the atmosphere also making the sponge air filter surface agitation unnecessary. But I'll keep them for now, the bubbles are soothing!
Thank you for sharing this video and the idea of flow being the holly grail has never stuck to me. I'm a believer that the beneficial bacteria are the key and my goal is to try and keep a balance between them and fish waste. Also liked the way you explained how it should work on a filter, independent of the brand.
I stopped worrying about GPH ages ago. It is a number meant to attract people, who put trust in products before they use them. I mean if you are new, often you don't know where to look, so you trust the ads.
I use Sponge filters with an HOB so two types of filters but I can make the HOB either a mechanical filtration with bacterial filtration, or it can be used with strictly ceramic media or as you showed, sponges. I like current in a tank so the combination of sponge filters and an HOB is an inexpensive way to get this.
I think Pond Guru got me turned into this a few years ago. Thanks Zenzo, good information!!
What are your thoughts on flow rates and filters?
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A slow filter is most likely the Best water purification possible, Reverse Osmosis units would be the simplest example, but as you said in this video, beneficial bacteria work Best with long exposure times.
Thanks For Sharing ✍
Great analogy! Love the food bit 😂
I definitely like this video,because I believe the slower flow rate definitely improves the aquarium by letting the bacteria do what it was made for.very insightful sir.
Another consideration with regards to flow rate through media is that if you have a very slow flow rate and a very large amount of media by the time the water has travelled through the media the aerobic bacteria would have used a large amount of the oxygen contained within that water giving you the potential to develop anaerobic bacteria farther along within the media therefore dealing with nitrate aswell as ammonia and nitrite. Provided the water is oxygenated on its return to the aquarium would vastly improve the health of the aquarium and inhabitants.
Your explanation on benaflital bacteria is right on the money good work
From the thumbnail I thought this was for tickets to the gunshow 😝💪
Loving the content as always 👌
Interesting video! I was going to listen to on way to LFS but nine plus inches of snow falling today.Jeff Miotke was in today giving an scaping demo,got to give the man credit besides the owner and store staff only four of us diehards made it. The man still did the from nothing to scaped tank and Oase bought lunch. After a very slow ride home I’m watching now.
Totally agree that GPH is not something to fixate on when choosing a filter. Media volume, inflow/outflow design and safety, even noise are probably more important things to consider.
I think you are correct. I use a diy top of the tank filter for almost 10yrs. Powerhead to top of tank box. Slows the flow compared to the aquclear 110 Bare bottom 4goldfish 60g tank.more sponges and quilt batting makes a gentler flow. Crystal clear water too.WKLY water changes 50%.I use a Co-OP ceramic media bag too!
Thank you functional testing, really cool
I mainly pay attention to the gallons per hour thing now because I want to know how strong the flow will be in the aquarium. Currently, I have aquaclear filter rated for a larger tank than the one I have so the flow is pretty strong and I don't think my neons like it so much. For next time, I might get a weaker filter or just go with a sponge filter. Though I don't like how much noise those air pumps make.
thx for helpful info on filters
I use sponge filters for beneficial bacteria and HOB to polish water at the same time for this same reason. also I prefer HOBs that have the flow adjustment for this very reason as well.
I totally agree. In nature when a creek has a rain running through and flow is increased the water becomes turbid and you can't see through it anymore. Water needs dwell time in contact with the media, and the surface area needs to be large enough to handle the fish load. Blasting the water through is putting the filter in cleaning mode, not filter mode.
I agree.
GPH should not be the deciding factor when buying an aquarium filter.
I am all about the quality and the features.
Couldn’t agree more. I’m planning do do a video about this also. Your fish room is sick. ❤️
I just have one big air pump and all my tanks on air filters, the pump is 35L/min, around 550 gallons per hour, running 11 tanks and could probably do a lot more. Very efficient and cheap to run! I like to make bottle filters with crushed lava rock and put a sponge on the bottom, and also run normal sponge filters on all tanks
This is interesting. I only have smaller tanks- what is the flow usually like in sumps or trickle filters?
I like knowing flow rates. Most fish I like to keep do better not being blown around the tank so I like lower flow and I only rely on hob if I need extra mechanical filtration. Flow is an important consideration with sumps especially so you know you’re using a well designed system as waters leaving the tank and being returned. It’s simply a metric to work with and not the whole picture.
It's actually funny when I think about when I first started keeping fish which was only two years ago I was super concerned about the water being super clean and running my tidal on the highest setting. Nowadays I pretty much have it tuned to about 20 to 25 percent flow and just vacuuming up whatever is left every week. I feel like I had to come to the realization that the filter would never get everything and my fish would be happier without all that flow, unless I was keeping hillstream loaches or something like that.
I've recently came back to the hobby and started on planted tanks. I've seen people saying "More flow better success". I never listen and you put a seal on my 40g breeder. Sicce Whale 500 flowing like an Aquaclear 50 and all of my plants look great and well the fish thriving....
The following theoretical situation isn’t proven nor real but could be used as an example with the logic you provided. One aquarium filter recycling the tank 10 times per hr and requires a certain part of water to be recycled twice to fully remove the ammonia and impurities in the water while another requires that same part of water to only be cycled once through the system to remove ammonia and impurities through the water but only recycles the tank 5 times per hour. Both of the filters will remove all the ammonia and impurities from the water just as quickly. The best product is one that requires only one cycle through the filter while recycling the tank the most per hour. Accomplishing this is simple, by using a wider path where the filter media is, the water will travel more slowly through the media allowing all the impurities to be removed in one cycle while having a high flow rate. The flow rate of water and the speed of water movement are not the same and creating a wider path reduces the speed of the water movement but not the flow rate. Once again, this is theoretical, not real.
As far as I've noticed, sponges do the trick just fine for bio. So, I've taken to HOBs and internal canisters for mechanical and chemical filtration. Haven't had any issues since.
Thanks Zen! residence Time‘s is what I call it. The amount of time it takes for the chemical reactions to take place. That’s what you want for biological filtration and general chemical filtration. Mechanical is where you want all the turnover very good video to break it down.
I do try to shoot for that 10 times per hour for water clarity though, the more you pass through physical filtration the more particles get picked up , most beneficial bacteria is on substrate and surfaces in the aquarium. The numbers filters give are with no media and no head distance
It’s interesting because I think that mechanical filtration primarily collects debris into its media and as that media collects, it either stays there until it is removed for cleaning or is consumed, partially or completely, by the bacteria. The gallons passing through shouldn’t be the primary calculation of filtration because the media does most of the work collecting it. If the media wouldn’t be there than some of it could cling to the walls of the filter or the pipes but for the most part everything moves with the water. The rate of flow could be used to see how full the filter is or if the motor/pump is struggling.
Interesting. Makes sense actually. I've always bought a filter with a flow rate one step higher than necessary for the size of the aquarium and I probably still will do that, but I may just slow the flow rate down and see what happens.
From experience I agree with this theory, I’ve found that it’s better to have a weaker flow with as much filter media as possible rather than strong pump and less media.
The only advantage with the high flow rate is it keeps detritus from building up in dead spots, however you can supplement with a power head to move water around and keep particles suspended till they get sucked in the filter.
I totally understand what you are saying but I think there is a key point you're missing out on.
As an example, my 75G running probably half of those filters you showed over time. I had a 55G and took everything from that tank and went to a 75G. Guess what..... The filter flat out didn't fit the rim. So then I had to go buy the one that had the spacing for the larger rim. Flowrate went up and I had so many issues with the sand substrate being blown away from the front of the tank because of how intense the flow is.
I generally prefer to run two 75g "flowrate" filters on my tank. The tank isn't set up due to some construction but ran for years with two of the tidal 75s on either half of the tank. I absolutely still had issues with the substrate moving, but the key factor being that the tidal has by far one of the best pump/impeller designs and the best flow control system of any filter available.
What I did to "fix" issues like the above was to side mount the filter and force the water to go the length of the aquarium. Think about it. It's a typhoon of flow, but we are told it should run 12-24" instead of the 36-48" on the length of the tank. More flow helps with more oxygen in the water, some fish demand that oxygenation. I focus my flow requirements on what the FISH NEED. The GPH is just a stat on the box because it's one way for the design engineer to state it's intended use case. Imagine a filter where the pump you used could be controlled by the user, or better yet, where the pump itself could be added after the fact by the user easily and was high quality. The HOB itself allows the pump to be adjusted, but the box supports a low, medium, high flow filter in any use case. You buy the box, you buy whatever "flow" you need, but you gain room for media and for sponges instead of having to be forced into A size by the tank.
That's why so many years ago all of those videos took off of people making their own HoB or modding HoB just to function better. Yeah, there is absolutely a disconnect between the designer of some of these filters and the managers of those filters (their goals) in comparison to day to day use by a hobbyist. Furthermore, as someone who can design things for a living, and who has been in the hobby long enough to know that the majority of the filters just don't work well, it's tough to see some of those design choices just to force replacement parts or to force replacing of low quality media.
Would be cool to see you do a video talk with Pondguru on filters. That guy has a massive amount of knowledge and some great videos.
I’ve gotta visit your fish room buddy!
I use the litre per hour to get a rough estimation about how much flow the filter can create in the tank. Not how effective it is. It is a pump after all. All pumps are labled with litre per hour values. Not just aquarium pumps.
Interesting idea. No idea if it works like that or not, but higher flow rates don’t always go well with the fish either, so yeah. Interesting idea. 🤔
The wildest thing about those gallons/hour stats on filters is that they measure them based on the rate when the filter is empty, not when it is full of media…so it’s an extra useless stat since nobody is going to run their filter without media in it.
I have AquaClear on my salts and tidal on my freshwater like both but tidal you can hang you heater I like that seems to spread Heat more evenly cause it next to intake tube both you can adjust flow rate
I am interested to see how your tests come out but right now I am not so sure the the speed of the water going though the media is going to show much. And not sure how exactly you would test this. My thought is the tank and everything in the tank is what houses the BB, yes it’s in the filters but I look at the filters as more mechanical polishing the water a place to put gfo and carbon
good job!
Interesting because I have been doing a little research into this , especially the anoxic filtration, which is not aerobic like the oxygenated water needed for our bacteria that converts ammonia and nitrites into nitrates but a very low flow ( under .05ppm oxygen ) and it is not anaerobic which is 0 oxygen often found in deep sand beds tanks . It is a very low flow low oxygen level that houses a beneficial bacteria that actually uses oxygen from the nitrates. The bacteria in these low flow zones consumes the oxygen from the nitrates (no3) in the water. Takes those 3 parts of oxygen leaving nitrogen that then gasses off harmlessly . It’s a bit sciencey for me but Dr Kevin Novak’s videos explains how this works a lot better than I ever could . That is how he runs all of his nitrate free tanks. The slower the flow and lower oxygen levels creates a totally different bacteria that actually consumes nitrates. Specifically his plenums or undergravel filters are known best for this process. It’s technically different to what you were explaining but it definitely is a interesting take on how bacteria works and how different flow levels and oxygen levels work in the aquarium 👍🏼
Edit - I do think the housing of the biological filtration is one of the most important rolls in our aquarium as well as The mechanical I guess , which is probably more for oxygenation and keeping poop and food etc particles out of the water. Interesting to see a different video with a different view and take on the filtration , Thankyou 👍🏼
I use a single tidal 55 on my bigger tanks with a deep sand substrate with lots of plants. I keep my lights on 10 hours a day and that seems to do the trick. I use a pre filter sponge on both from aquarium co-op of course, with more sponge and poly fill in the basket. In my 10 gallon tanks deep substrate and a single sponge filter with plants and lights the same as the other tanks. They all look good and waters tests just fine. I think some good filtration happens in that substrate. But I'm in agreement with the gph. If you run all your water through that filter at least once an hour you should be all right. There's tanks out there right now that have no filtration at all and doing fine. Just saying.
Liked the topic.
👍😎 Same kinda thinking as Jason (Pirme Time) who is way more knowledgeable than most of us when it comes to aquariums. He rinse’s his media in tap water because the chlorine doesn’t have enough time to harm enough bacteria to be considered with. Never thought of that when it comes to filter’s. Interesting. 🖖
I think it was LRB, showing off a filter that he wasnt sure if it even worked it had such large plant growth. But i packed my hang on back with plants to slow the flow as well
I'm more about total media surface area and less about flow rates. I'll purchase my filter, or adjust my flow rate, for the particular aquarium and fish.
I have a 10G with shrimp so I have a little HOB with sponge, filter floss, and crushed coral. It slows the flow. On the other hand I have a 40G with 2(1 year old) turtles, 2 albino plecos, 2 red blood parrots, some Cory cats(5-6), and a handful of guppies and zebra danios. On that I’m running a 110 fluval aqua clear with sponge, bio balls, and some crush coral plus another little “turtle” filter in the water and a sponge filter. I want a good amount of water flow to keep the water clean and clear. The waste from the turtles and plecos is pretty good size so need lots of flow. The little inner filter is set on a timer so at night it turns off and I usually put the big 110 fluval on low to give the fish calmer water at night. I do weekly water changes and nitrates stay below 40. No plants since the turtles and plecos and Corys uproot anything I plant :( next year once I move I’ll be getting a bigger tank for the turtles.
I totally agree with you. But how about moving bed filter ? The flow rate need to be strong in order to cause the media to move. Does that really create benefital bacteria?
With a moving bed filter, the flow is actually not that strong (water in and out), and the media is submerged in the water it’s “treating”, so theoretically in contact longer. Great question/point though!
I agree with you with the exception being if someone have deep substrate, driftwood and plenty of surface area to harvest bacteria, then it won’t matter much. The amount of media you can store in your filter would probably make more of a difference if the nitrogen cycle is your main concern. If I’m spending all that money for a filter I am definitely concerned with gallons per hour because the only real advantage of having a canister or HOB versus a sponge filter would be water polishing. I could just put a bunch of lava rock inside the tank if I want to harvest bacteria.
Totally agree with surface area with sand bed depth and rock. Drift wood is spectacular in that it not only has the external surface area, but with its absorption of water, it has both aerobic and anaerobic properties for full cycling. Thus the high flow rate is important for continuous water movement over the whole tank, creating current for fish to swim against, and suspending solids for water polishing.
Haha what I did for my first tank. I did all this research on substrate that produced the most bacteria and give places to hide to those bacteria. Totally went all out with a black volcanic rock substrate tank. With red lava rock used for grills as decorations.
Note: I do still run an air filter just in case something dies. My tank is very overstocked.
Flow rate tells you more about how long it takes the filter to slow down than anything else, sooner or later the rate will even out no matter how powerful the filter is.
Lol....was waiting for the big reveal or 2. You did not recommend a filter based on your findings. But a great video.
What kind of fish is that at the 1 minute 10 second part in the video it looks really cool!
African Mudskipper. You can see a recent video I made on these fish here: ua-cam.com/video/TAbLKFRk1pc/v-deo.html
Thank you so much !
Eheim has been sizing their filters this way for decades; flow designed to maximize the nitrogen cycle, while still creating enough flow to mechanically filter the water. Remember trickle filters? Slow moving, highly oxygenated water that swallowed all the ammonia and nitrites. Wrongfully called nitrate factories because people didn’t clean the mechanical filters enough. Keep your bb clean by cleaning the mechanical media often.
Some of us use two filters for this very reason; a slow one for bio and a quicker one for mechanical. The slow one also clogs less… which is perfect.
An example of apples to apples: two sponge filters in the same tank. One is very coarse, doesn’t trap much, and has the airpump set on low. The other is fine, catches everything, and has the airpump set on high. One for bio and one for mechanical. Clean the the mech. one frequently.
Theil (Thiel?) wrote some great books/articles on this in the 80s as did Moe.
i go if you have 100L tank take 200L filter and slow it down works for me for now last year i didnt clean filter becouse it is nothing to clean having sponge filter on inlet and everything is stucking to foam
The upside of the gallons per hour is the current it puts in the tank. Many fish live in very active rivers and we don't do a very good job replicating that current in the hobby. Wave makers for example are generally used in salt water tanks. The higher water flow filters do a better job replicating this as well as how heavy they oxygenate the water. While it isn't the be all end all stat for a filter I still think it is very important
If you put as much media as you possibly can in to a to a tight bag and stick it in your filter/sump the water will flow really slowly through the center of the bag great for beneficial bacteria
I use sponge filters and hang on backs. Sponge filters for biological filtration and hang on backs for mechanical. I don’t like using just sponge filters because they don’t do a good job of mechanical filtration in my experience. I think some large particles get trapped in the filter of the hang on backs. There, the bacteria can break it down.
Thanks for sharing🥰🇮🇩
U make a lots of Sense
Sometimes! 😆
I think brand, flow rate, the amount of filter media (size) are the only ways to evaluate filters that aren’t sponge filters. Even sponge filters are compared by size. I firmly believe buying a filter capable of doing 10x your water volume is a good metric bc the manufacturers measure GPH without any media. When we stuff every possible nook and cranny of our filters with media, we can effectively halve that flow rate.
Other things to consider: available parts, power consumption, self-priming or manual priming, capacity to add more media, ability to modify, ability to alter flow rate, easy of cleaning, etc.
Keep it up.
I agree and I'm pretty sure the science backs you up
I do believe flowrate is a factor in filtration.
But not as much as brands make it appear in their marketing.
First of all, all the flowrates need to be cut in half anyway cause they are measured without media in the filter.
And depending on the type of media it slows down significantly.
So im with you on that.
The other side
I dont think the aerobic bacteria have trouble with higher flowrates.
I mean its how moving bed filters work.
There is constant chaotic movement and the filters break down ammonia without issues.
I believe that what you describe is more a factor with Anaerobic bacteria.
They need slow moving water with low levels of oxygen to break down nitrate to nitrogen.
And if you got a massive filter with high flowrates with media that lets water pass really fast.
You never get a full nitrogen cycle.
Contact time between the bacteria and the ammonia or nitrate
I've talked about this with some old timers, and they say the faster, the better to ram water through my cannister filters, even for biological processes, I on the other hand think to slow it down would help with biological processes in being in contact longer with my bio material would be a benefit. They all disagree! Only thing I can say about that is maybe the split second or so gained by slowing the flow doesn't help. I'm not a chemist!
I have never payed any attention to filtration flow rate. It is the tank that will tell me what it needs, the flow rate of my filtration all gets worked out during the time I am balancing the tank out and yes it does take time. My flow rates will change as needed through this process and eventually I will end up with the perfect flow rate that is good for the fish, good for the plants and good for filtration. Each tank is different, in reality there is no one size fits all just some general guidelines. Your tank will tell you what you need, learn how to recognize what your tank is telling you.
This is what Ozponds says when building a bog filter for ponds too.
if that is the case slow your filter to 1 gph and see what happens. There is a happy medium between flowrate and a good environment. This will differ in all cases because no two aquaeiums will ever be exacrlty alike. The more you process water through a filter media the more solid waste it will remove quicker. The more water flowing means even heat distribution throughout the tank. if you dont have sufficient bacteria to handle the bio-load of the tank putting water through a filter will not remove ammonia. I use cansiters and sponge filters in my tanks so I get the best of both worlds. Sponge filters work well, they strain the particulate matter while giving bacteria a place to colonize. Canister filters do the same thing on a vastly ;larger scale and they agitate the water better for more 02 exchange at the surface. Warm water does not hold as much O2 as cold water does so you need even more agitation in a warmwater tank depending on the amount of fish you have vs surface area. Sponge filters are great for jump starting new tanks as well. I fishless cycle my tanks with straight ammonia from day one so I never worry about bio load when my fishless cycle can deplete 2-3 ppm of ammonia within 24 hours i can dump a ton of fish in a tank and never have an issue b ut doing it this way can take 3-5 weeks sometimes. Using a s cycled sponge speeds it up a bit but not by that much in my expirience. Nature takes time and when you mess with it you get messed up results. Sumps are great filters and have massive contact to water flow time due to the fact they are just gigantic canister filters . At the end of the day will a small canister filter meant for a 55 gallon tank work on a 100 gallon tank, sure it will. Would I use that if I had to , sure, Would one with a better flow rate and more media be better, YES. How much better is the question but at the end of the day who GAF when the price of the next size up is 30-50 more dollars. In the grand scheme of things when you are dealing with hundreds of dollars of fish are you willing to skimp on filtration to begin with? The whole discussion ends in a meaningless waste of time
I think the flow rate is the impeller motor itself. No intake tube. No filter.
Great video. There was a time when under-gravel filters were king. This whole GPH myth is just that, a myth. It's something that was invented to market the very first powered filters over the use of under-gravel filters. The most important part of filtering water is biological, where a low flow rate is key, everything else is secondary. Fish husbandry went hand in hand with UGF by siphoning any wastes in your tank, thus acting as a mechanical filter in conjunction with the biological filtration from the UGF. The problem with today's filters is they try to be all in one, making the fishkeeper a lazy fishkeeper and putting husbandry on the wayside. My preferred tank filtration is still UGF, but now with my DIY canister filter heavily outfitted with sponges, EHEIM Substrat Pro, and my DIY Chemipure. I also use a water flow meter on my canisters to tell me when it's time to clean my sponges. Whatever filtration one chooses, fish husbandry should never be a byproduct of your filtration.
I hate to say it but we're overthinking this. Water moving fast or slow doesn't change the ability for biological filtration to take place, at least not in a way that's meaningful to an aquarist. We did experiments like this in college but rather than commercial filters we used lava rocks and a sump. The first stage was simple over flow with a small return pump. We progressed in stages until there was a huge pump in the tank and the sump and it was a whirlpool in both. It wasn't until that point that there was a meaningfull difference but that is far about flows the hobby would have. Our hypothesis was that the flow was so strong only aerobic filtration was occurring. However, it was never tested
That also depends fish u are keeping
Advertising the GPH is very important when buying a filter.. imagine buying a car and having no idea if it’s a 4 cylinder or a v8… it’s necessary
I am by no means an expert but I think there is a lot of fashion in this hobby that is accepted as fact: you must have 10x turn over flow filters, canisters are the be all and end all of filtration, you must use the most PPI media available to science and everything else is useless. My experience and therefore my opinion is all of this is not true and is more fashion than fact.
👍🏻😎
I'm wondering if it'd be feasible to use two filters. Here's my logic. Use one filter that is big enough to use slow flow to biologically filter the water, and a second, maybe smaller with a higher flow rate to polish the water and suck up any solid waste. I'm thinking that if the bio filter is slow enough, it's not going to suck up as much solid matter, and therefore not get clogged/cleaned as fast,. And then you just have to clean the smaller particulate filter that will suck up mass quantities, and polish the water.
The issue I have with it is that you have two things plugged into power. For my personal use, I'm thinking of building a custom sump where I only have to really worry about one pump, and cleaning the particulate filter. For somebody that doesn't have the space to put a sump for example, would two separate filters for different uses be feasible? I'm talking about power, space, cost?
Many people use a hob and a sponge. 2 is fine. There are very few instances where you can have too much filtration.
Two filter are alway the way to go for the point made and for redundancy. If one filter becomes clogged or fails you still have one on the job.
5 second rule clip lol