How to Calibrate a pH Meter - Testing Kit with calibration powders and standard solutions
Вставка
- Опубліковано 5 жов 2024
- In this video, I'm sharing how I calibrate my pH meter. It's a cheap one, so I don't expect it to be too accurate, but I wanted to share my process.
To do a basic push button calibration for this particular pH meter, two points are needed, so you'll have to use two calibration powders (6.86 and 4.00). During the process, I wasn't able to get the calibration to be accurate to 0.01, but it is accurate enough for my needs. Since the pH meter measures electrical conductivity (EC) of the solution and then converts it via an algorithm to get the pH value, there's some inaccuracies as it heads towards the alkaline, high pH range (from pH 7-14).
I kept this pretty simple and easy to follow, but if I was unclear about something, let me know in the comments below!
Like what you see? Please support my channel so I can do more reviews like this in the future and buy me a coffee: www.buymeacoff...
---
Growing Environment
Orange County, Southern California (USA)
Zone 10B: Subtropical/Hot-semi arid climate - hot, dry summers / mild winters with low to moderate rainfall
Average Summer Outdoor Temperatures: 63-83F
Average Winter Outdoor Temperatures: 48-70F
Average Rainfall: 13 inches/year
Indoor Temperatures: 65-85F
Indoor Humidity 40-60%
East/West facing windows
---
THINGS I USE:
Self-watering pots: amzn.to/2Fl5lAm
Sphagnum Moss: amzn.to/2FlqZVx
Seedling Bark: amzn.to/2FjH8dH
MSU Fertilizer for Well Water: amzn.to/2RfKTne
Nutricote Slow Release Fertilizer: amzn.to/33kwQlI
Seaweed Supplement: amzn.to/3ikIdR0
Silica Supplement: amzn.to/2GLYS21
Miticide for Spider Mites: amzn.to/2FlAIuO
DISCLAIMER: Links included in this description may be affiliate links. If you purchase a product with the links provided I may receive a small commission. Thank you for supporting Attainable Green so I can continue to make awesome content for you to enjoy!
#pHmeter #calibration
One does rarely see the same amount of energy put into replies to viewers comments, compared to the video itself. You really raise the bar here. Thank You!
You’re welcome! I try my best to answer questions in case I missed something that wasn’t covered in my videos. Thanks for stopping by! 😀
Thank you for this. I love when someone making the video runs into issues and rolls with it and discusses why it can happen and what can be done to fix. Again, thank you for this.
You're welcome! I do my best to share what I know, the good and the bad. In this case, it really just didn't work for me...so it is what it is. 😂
@@AttainableGreen Yup... that's how it goes. I tried to calibrate mine (same pen, I think), and ran into similar issues. A lot of wonkiness with testers at this price point..... but I guess I'll work with it for now. Like you mentioned, it will read to 0.1 accuracy and that's ok for now.
You add 250 grams of water (close to 250 mL)
The pH scale is logarithmic so there is a big difference between a pH of 7.0 and 8.0: in fact a 10 fold difference (or order of magnitude). A pH of 5.5 is not 10% less acidic than a pH of 5.0.
Great video! So useful! 👍🏽
Thanks! Glad it’s helpful for you 😁
Umm.., for some reason, pH depends upon temperature. Most unbuffered calibration solutions need 77°F temp for accuracy.
Very helpful I'll keep this in mind if I ever buy one of these
Hi, thank you for your instruction video about the calibration process of this pH-meter. I've bought one myself, and it's on his way to be delivered. I have one question regarding the buffer solutions. The powders to make these buffers come in the package with the meter. Once they are dissolved (buffer solutions made), they can be stored for a while (if you are taking care of them, by not carrying over droplets from one solution to the other, for instance while calibration). But eventually they will go bad over time. I work in a lab environment and have easy access to other buffer solutions, but these are of a different pH value. Do you think it's possible to adjust the value of the pre stored buffer in the memory of this pH-meter, to the desired pH of the buffer solution? I see only two buttons, so I guess not? Thanks in avance for your answer.
This is a very simple pH meter so it doesn’t have much flexibility in calibration solutions. If the buffers in the package go bad, there are options to purchase more in powder or liquid form. The calibration function only works with the pH of the buffers mentioned. In a typical lab environment, it’s best to calibrate the pH meter each time before use. In a home/personal setting, the pH meter can still be used if not calibrated every time, but fairly regularly or often to ensure accurate readings. If the calibration solution pH drifts, the meter will compensate for it over time until it becomes ineffective. Then, the meter will display an error during calibration. So, no, there is no way to adjust the value of the pre-stored value of the buffer in the meter. I hope that answers your question.
@@AttainableGreen Thank you for your fast and extensive response. It is indeed what I expected more or less, that there is no possibility to use other pH buffers than the ones that come with te pH meter. I think I will use the provided buffers as long as possible (by taking good care of them). It's not always necessary to calibrate a pH meter in a lab environment each time before use. In the lab where I work we do a quality control check with a different buffer solution than the ones that are used to calibrate in the first place. If it has an acceptable tolerance, we don't perform a calibration, otherwise we do (of course). I will do the same with this meter: use the solutions provided with the meter only to calibrate, use the other buffers (i have pH 4.00, 7.00, 9.00 and 10.00) to do a QC.
@@dvraemdo You are right. You don't have to calibrate every time, but at least make sure the meter is working accurately and that it's within range of acceptability. Thanks for sharing your knowledge and expertise! :)
Did you store the solution you made originally? I just bought a similar yellow ph pen. I’m watching your video because I want to calibrate it correctly, but I’ve been realizing that it’s good to test it and recalibrate it once in a while. It came with three envelopes, a ph of 4, 6.86, and a 9.18. I’m wondering if I can store the solution and keep using it to test my ph pen in the future.
Yes, you can store the solution for a few months. Depending on your environment, the pH 9.18 solution will go bad first and the ph4 will last the longest. I would say, conservatively, to get a new batch every 6 mos - 1year.
I just picked up a HM Digital PH-80s that I haven't tried yet but I've always used Bluelab pens in the past and would definitely recommend them if your budget allows.
Thanks for the tip! 😁
Wow great vid. Can you do a video on testing your water quality (pH, TDS, hardness, etc.)? What parameters do you aim for when you water your orchids?
@@AttainableGreen Thanks for the response. I am slowly understanding the chemistry behind it as I look up blogs, watch vids, and read articles about water quality. My tap water is very hard and alkaline where I am currently living and my cattleyas are not thriving as they were at my last place. It's bad and good....but in the end I am evolving as an orchid grower.
If u use this for plants, just use the 6.86 not all three. Calibrate every month to two times a month, never let the probe dry, Been using these things fir over 15 years in hydroponics
why?
Hi!
I found your video very informative!
Btw I need a bit of help, I need it to measure ph of milk while making cheese so how many times in a month should I calibrate? And can we reuse ph solution liquid next time? If yes then how long can we store the ph solution and any specific instructions on storing it?
Thanks 😬
There’s no set schedule to calibrate. Best practice is to check that it has accurate readings before use and if it’s deviating from the standard or expected reading, then calibrate. You can reuse the calibration solution and it can last for about 6 months - 1 year. Proper storage would be to have it in a lidded container in a cool dry place.
@@AttainableGreen thankyou 😄, I have the powder thing in a sachet the one you have in the video, the solution made by it will last upto 6months too right?
Yes
@@AttainableGreen thankyou so much 😀
I'm not exactly sure about the fact that calibration with 3 buffer solutions will give you better accuracy, and I'll try to explain why. With this meter the pH is measured as potential difference over a thin layer of glass. So actually its a 'voltage meter'. Now, the realationship between the measured voltage and pH follows the 'Nernst law'. In an 'ideal world' there is a linear relationship between the measured voltage, and the actual pH. But that's the theory. Normally you calibrate first with a buffer solution with a pH of (around) 7, to know the 'offset' (or zero), and then you use a second buffer (to determine the 'slope' of the linear relation), either with a pH higer of lower than 6.86, depending of the pH range you are measuring in. So, for instance if you calibrate with 6;86 and 4, you wil get fairly good accuracy when measuring between or around these values. But if you want to, for instance, measure a solution with pH of 10, the accuracy won't be that good. In the video you were performing a 'three point calibration', and I'm not exactly sure what the meter internally does with these values. That's why I think you got an error during calibration with the buffer solution of 9.18 because the meter can only draw a 'straight line' between the pH of 6.86 and 4.00, and the 9.18 falls out of tolerance.
Thanks for your thorough explanation! I was going off of what the directions indicated for more precision readings. True, I have learned a bit more about how the algorithm inside the meter works since this video was posted and yes, you are right about the calibration calculations. :)
In all these videos I watch none have addressed the issue written in the instructions of drying the probe with filter paper between dips. What actually is filter paper? Well I'm thinking coffee filter paper might be fine as not to spend a bunch on something more exotic. I'm about to calibrate my Vivosun meter I recently purchased. I'm using mine for an aquarium so I'm sure it will be good enough.
Most instructions are written with a lab environment in mind and filter paper is commonly used as a drying agent as it doesn’t leave fibers or residue behind. For general use, coffee filters and paper towels will do the job. Thanks for checking out my video 😄
Hi. Thanks for a detailed video. I have a similar PH meter which I have not used for over a year. I took it out and tried testing my tap water it just say '0000'. Do u thing the electrode has dried out ? If yes how does one rehydrate it?
It could be that it needs new batteries. Otherwise, if it’s the electrode, then a soak in some acidic solution (calibration solution pH4) may help. Submerge the electrode for a few hours and then test.
@@AttainableGreen thank you. Will try
did grate
Hello, very good video 👍.
One question: can we keep the different solutions made with the powders as pre-made solutions for future calibrations? Do these solutions drift also in time? I guess so....
Thx
Yes, you can keep the calibration solutions for future use. With a good airtight lid and proper storage, the acidic solutions pH 1-7 may last 6 months but anything over pH 7 may last about 3 months since it will degrade the fastest. The light and air exchange in the storage solution can cause them to drift over time.
@@AttainableGreen Great!!! Thanks for your prompt reply 👍
Mam would you like share your WhatsApp no with me so that I can get help from you in this regard .thank u
Unfortunately, I do not have a Whatsapp...but I will do my best to answer your question.
@@AttainableGreen thank so very much mam.
Hello, do you have to keep the electrode moist between uses? Like do you have to add a few drops of some liquid in the cap? I've seen some say you should keep it in distilled water, or in the 4.01 buffer solution. I'm not completely clear with this. Thank you!
For this particular model, it can be kept dry. But in general, it’s good practice to keep the electrode slightly moist between uses to extend its shelf life. You can use a designated electrode storage solution or pH 4.01. Do not store it in distilled water long term as it can leach out the electrode and give improper readings.
When i try to calibrate it either says 0000 or 0.06 but nothjng i do seems to have any effect
If it’s a brand new meter, it shouldn’t have any issues. If the reading never changes, then it may be time to change the batteries or get a new meter if it’s not working properly.
@@AttainableGreen i figured it would be one of those, i'll try replacjng the battery to see if that does it
I had this exact same problem, my new cheapie flash 0000 when trying to calibrate.I changed batteries and it worked.Was driving me crazy because nothing I did had any effect.
Are you sure you shouldn’t calibrate on 4 first? My meter seems to start off at pH4 when calibration is pressed.
Some meters have different calibration procedures. The instructions on this one does not start with ph4.
How much solution powder do you need to use? The whole packet?
Yup, use the entire packet.
@@AttainableGreen actually i think if you cut the amount of water in half, and used 1/2 a packet(accurately divided), you would probably be fine. (1/2 packet and 125ml Water)? Water temp also matters, which you didn't mention. Couldn't you do less than 2 solutions by just stopping after calibrating to the pH 6 solution? (At the cost of higher accuracy).
Mike Blank Thanks for stopping by! You are right, two solutions is enough accuracy for most measurements. This video is my attempt to explain how to calibrate, so it’s not comprehensive and I am bound to miss some things. I appreciate your comments to make this video better and more thorough. 😄
@@AttainableGreen yeah it was a great video- I've never calibrated before, but have to soon, so I've been looking into it a bit. Couldn't you calibrate and then check the pH of vinegar and document what it's supposed to be, instead of the pH 7 which degrades, since vinegar stays for years? And could you just add/subtract the difference when you measured the pH 7 solution- so you know how far off your meter is, then just adjust all the values by that amount- so you don't have to calibrate? Kind of like using/not using the "tare" function on a digital scale- you can just subtract the weight of the empty tray/container instead of pressing "tare". Would it work the same?
@@AttainableGreen great video though :)
Hi, do you need to use distilled water or can you use reverse osmosis water?
RO water is available too me, however, distilled isn't.
Thank you :)
Mm, I am not sure. Usually in a lab environment, distilled water is used. If you’re using it for home purposes, I think RO water should be ok to make the calibration solutions.
Did using RO water make the water tester work properly? Also how many stages does your system have? I own a 3 stage RO system.
I used distilled water for this video. RO water can work as well and as long as the system works, it doesn’t matter how many stages are in the RO unit.
My ph meter got water in it, now it’s giving inaccurate readings... I cannot Calibrate cause it’s not measuring anything right
If the pH meter got heavily waterlogged, it may take a few days for the meter to dry out. Once dry, you can check again to see if it can be calibrated...otherwise, the sensors may have been damaged and will not give accurate readings. If that’s the case, then a new meter may be needed.
What about temperature of the water?
Ambient room temperature is good enough
If we turn off the meter then turn it on again it will remember the previous settings or it has no mechanism to store the settings????
It will remember the settings if the meter is off.
If suppose pH meter isn't accurate when calibrating pH 4 buffer powder . What to do ? Then use yellow screw driver to adjust pH meter to 4 , right ?
If it’s a new meter, then adjust the meter to 4. If it’s an older meter, you could try cleaning the bulb gently with a cleaning solution or dissolving the buildup with ph4 buffer for an hour or so before recalibrating again.
Magkano po yang ph meter at saan mabibili po salamat po
How do reset a ph meter
What if you just want to test the pH of bottled water tap water do you have to use the powders or will it work without
If you get the meter right out of the box, it’s best to use the calibration powders and make sure it has accurate readings before using to measure the pH of any solution. If you do not calibrate it beforehand, it may not give the correct reading.
Which one will be the best ph meter for testing laundry detergents that lies in moderate price..would u like to share with me?
Why does my meter read "end" when trying to calibrate the 4.0?
If you’re using the same model, it should read “err” for error. Usually errors come from improperly made calibration solutions, damaged or dirty electrodes, or low batteries. Not sure which one applies but maybe more troubleshooting might be needed.
Thank you. I bought two of these from Alibaba "XINGBA store", it's very useful.
Do you always need to rinse it off with distilled water?
The best way to preserve the electrode in the meter is to keep it free from deposits or residue. Rinsing with distilled water will help with that. It’s up to you how to care for your meter and how long it will last.
Where did you buy your distilled water?
I got my distilled water from the local supermarket.
@@AttainableGreen Thanks for the fast reply! Looks like I have to do an extensive search for distilled water next time I go to the Market.
How do you get extra powder to re do the test
You can order online, I got some extra from Amazon
Hi, If you change the order of the buffer calibration, starting with the 4.00 does it makes a difference? Because mine doesn't seem to be working so good :c.
Usually you want to calibrate according to what the instructions say because the algorithm will compensate for any irregularities. If you do it out of order, it may not be as accurate
Hi ..I am running my own business of laundry detergents and I am facing the problem how to test the pH value of the this powder using the pH meter.I want you help me in this regard . I will be waiting for your kind response. Thank u
Hmm, interesting question. When using this pH meter, it’s only for solutions. To test the powder, you would need to add water to it and measure the pH in the solution. For example, use 5g of powder and 100ml of water. Then check pH of the solution. Repeat for other samples. This is a simple way of doing things, but I am not sure if this is the best way to test the pH of powders.
@@AttainableGreen thank u.it is OK but if I put 5g powder in 100 ml water from 50 kg bag and test its pH then can I consider this pH value for the whole 50 k bag?
There are a few ways to go about it depending on what you’re looking for to measure. If you’re looking for the pH that the consumer would use at home, then make a solution at the recommended concentration/dosage of detergent and then measure the pH. Please note that the pH will change depending on the pH of the tap water or water that is used. If you have a detergent formula that has unknown ingredients and need to figure out the final use concentration, you can do a pKa titration to figure out the correlation between pH and concentration of detergent. If you have a known formula, you can look up the pKa titration curves and figure out the theoretical pH. Good luck!
@@AttainableGreen thanks for your nice reply...
Aquele mega positivo
gracias!
Hi...
Can I use Demineralised water for test..?
Yea, I think it should be fine.
Thanks
From your description: "...so I don't expect it to be too accurate". WTF would I watch this video then?
@Danny If it had read: "...I *didn't* expect it to be too accurate", then that would have entirely changed the meaning to that. :)
Hello, I have a question, when the pH meter is calibrated correctly and you switch it on does it always have to read zero? Because I calibrated it but when I turn it on it always reads 16 at first. Thank you.
It does not always read zero when you switch it on. Sometimes it may have some residuals on the probe and it’s reading that...so make sure to rinse the probe before use. 😁
@@AttainableGreen thank you very much for your answer, however no matter what I do it reads 16 but when I test it with the calibration liquid it seems to read it ok 🤔
Anna Nicky As long as it reads ok once it’s in liquid, it should be ok 😁
@@AttainableGreen thank you, lI hope so😀
Not to mention, throw it out an replace it every 7 months to a year
Mam..if I wana test my detergent powder pH in water then would I mix the calibrating powder ?
The calibration powder is used only to calibrate the pH meter. After calibration, you can test your detergent.
@@AttainableGreen ok thank u
@@AttainableGreen madam if i calibrate the ph tester using calibration powder then can i test ph of my washing powder upto the ph level of 11 and above?
Yes you can
@@AttainableGreen ok.aap ka bahot bahot shukria.you may live long
Not everyone has extra packets of buffer powder like you do. This is not a real life test. I hate the vivosun probe. It's horribly inaccurate.
How long did it take for it to start drifting?
It depends on frequency of usage. I noticed it drifts after 6 months or so. Depending on how accurate you need the measurements, it’s good practice to calibrate and check for accuracy with every usage session.
@@AttainableGreen mine started to drift 1 month after use :( my water is 7 and all the sudden it said 9.
That’s ok. There’s a lot of factors that can cause the meter to drift. Temperature and storage conditions can affect the meter. Best practice is to check and calibrate before each use (that’s what they do in labs) but for home use, we can usually get away with calibrating it less often.
@@AttainableGreeni bought a platinium ph meter now. it nearly killed my crop this time i only found out because i calibriated it on my own and saw it had driften from 7 to 9 in my tap water, my tap water is 7 but i add all kinds of things to the water so i cant never be sure.
Oh I see. A lot of variables can affect the pH of the water. Hopefully your new meter will work better for you.
There is no need for the three steps all you need is a 2 steps and get rid of this cheap pH meter.
does it work for growing marijuana, just need between 4 and 7 xD
Yea, it should work for a pH between 4 and 7
Wow all that work for a crappy meter spend a few more bucks and get a decent meter where all that testing to just calibrate is done with one solution period
Shit is so fucking confusing
Trash meter. Don't waste your money.
“A premade solution “ Wow… um. NOT HELPFUL. How do we make the magic solution?!
Some pH meters come with the calibration powders where you add water to make the solution. Otherwise, if you want a very accurate calibration, ordering pre-made standards solution (calibration solutions) is common practice in a lab environment.