Cheap But Reliable pH Meter

Renfro

Well-Known Member
Ok, I wanted to have some extra pH meters so I didn't have to keep walking from room to room to track down my bluelab. I picked up some of these cheapos from amazon and I must say I am impressed.

I have used three of them for up to a week without re-calibration and since I didn't trust them yet I used them side by side with the bluelab. I have been very pleased with their accuracy and stability, every bit as good as a blue lab and you get 2 points of accuracy. Had times the yellow pen read something like 6.68 and the blue lab read 6.7 so not having it round the numbers is nice.

I wasn't impressed with their calibration powders that you have to mix up. The meters use a 6.86 calibration solution and I found a bottle on Amazon. That was the only real hiccup with these meters.

https://www.amazon.com/Accuracy-Measurement-Household-Drinking-Aquarium/dp/B07RY488QV/ref=lp_5088419011_1_2?s=industrial&ie=UTF8&qid=1564932491&sr=1-2

https://www.amazon.com/gp/product/B017KP6AKQ/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Anyways, I wanted to share this find.
 

Renfro

Well-Known Member
TBH the more I use these the more I like them, The reading stabilizes way faster than the bluelab, almost instantly and they are very accurate. I am really impressed. I couldn't possibly stress how hard I am to please and these please me. Everytime I go to calibrate they are within 0.05
 

OldMedUser

Well-Known Member
Sounds like the BlueLab needs a proper cleaning.

My pH pen, EcoTestr by Eutech/Oakton was really slow to stabilize so I used a 2-part cleaning sol'n on it and now it's really fast in comparison.

I rarely use my pH pen and it had sat on the shelf bone dry for about 3 years. It's at least 7 years old now and after soaking in storage sol'n for a couple days before using again has worked fine.

I buy the pre-made liquid calibration sol'ns in 4 and 7. Same for the ppm pen tho 1000ppm.

I also keep the pH pen on the same spot on the top shelf in the grow room so I never have to go looking for it. ;)

:peace:
 

1212ham

Well-Known Member
Ok, I wanted to have some extra pH meters so I didn't have to keep walking from room to room to track down my bluelab. I picked up some of these cheapos from amazon and I must say I am impressed.

I have used three of them for up to a week without re-calibration and since I didn't trust them yet I used them side by side with the bluelab. I have been very pleased with their accuracy and stability, every bit as good as a blue lab and you get 2 points of accuracy. Had times the yellow pen read something like 6.68 and the blue lab read 6.7 so not having it round the numbers is nice.

I wasn't impressed with their calibration powders that you have to mix up. The meters use a 6.86 calibration solution and I found a bottle on Amazon. That was the only real hiccup with these meters.

https://www.amazon.com/Accuracy-Measurement-Household-Drinking-Aquarium/dp/B07RY488QV/ref=lp_5088419011_1_2?s=industrial&ie=UTF8&qid=1564932491&sr=1-2

https://www.amazon.com/gp/product/B017KP6AKQ/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Anyways, I wanted to share this find.
I might try one of these. I like the digital calibration, won't drift like the little trim pots. One could probably make some 6.86 calibration solution from 7.0 solution and a little ph down, or other acid?

BTW, if a meter is slow, the probe needs maintenance. Mine is as fast as ever after a 5 minute soak in dish soap and a genital cleaning with a tooth brush.

EDIT: I see that meter has both a calibration button AND a "correction potentiometer" on the back, how does that work??
 
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ChiefRunningPhist

Well-Known Member
@Renfro
Right on man! I do the same. I buy 3 @ a time. Lol it's nice to have a few laying around I agree. The thing I notice is when the batteries get weak they get sporadic, but the batteries stay good for me for at least a whole grow. They so cheap, why bother to buy new batteries when you can get a whole new pen?

I use 3 jars and bottled Aquafina. 1 jar is pH calibration solution and has lid so it doesn't evaporate. 1 jar is the storage jar and has just enough water to cover the sensor bulb when I place the pH meter in the jar to soak & store. The last jar is about half full of purified water and used to rinse off the pH meter (from the dirty nute water) before placing in the storage jar. Before any test I do a quick calibration in the pH solution and then do whatever tests I need to do. I change the water out maybe 3× a month.
 
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ChiefRunningPhist

Well-Known Member
I might try one of these. I like the digital calibration, won't drift like the little trim pots. One could probably make some 6.86 calibration solution from 7.0 solution and a little ph down, or other acid?

BTW, if a meter is slow, the probe needs maintenance. Mine is as fast as ever after a 5 minute soak in dish soap and a genital cleaning with a tooth brush.
I use to use vinegar as my calibration solution (2.4). If you used pH down and purified water I think that you could make your own. I'm guessing if you used tap water you'd get drift over time but idk..
 

vostok

Well-Known Member
Ok, I wanted to have some extra pH meters so I didn't have to keep walking from room to room to track down my bluelab. I picked up some of these cheapos from amazon and I must say I am impressed.

I have used three of them for up to a week without re-calibration and since I didn't trust them yet I used them side by side with the bluelab. I have been very pleased with their accuracy and stability, every bit as good as a blue lab and you get 2 points of accuracy. Had times the yellow pen read something like 6.68 and the blue lab read 6.7 so not having it round the numbers is nice.

I wasn't impressed with their calibration powders that you have to mix up. The meters use a 6.86 calibration solution and I found a bottle on Amazon. That was the only real hiccup with these meters.

https://www.amazon.com/Accuracy-Measurement-Household-Drinking-Aquarium/dp/B07RY488QV/ref=lp_5088419011_1_2?s=industrial&ie=UTF8&qid=1564932491&sr=1-2

https://www.amazon.com/gp/product/B017KP6AKQ/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Anyways, I wanted to share this find.
Learn to grow without this CRUTCH: organics is a start
 

OldMedUser

Well-Known Member
I use to use vinegar as my calibration solution (2.4). If you used pH down and purified water I think that you could make your own. I'm guessing if you used tap water you'd get drift over time but idk..
That is just cray-cray.

Cough up a few dollars and buy some real calibration sol'n. Unless you grow your plants at pH 2.4 then carry on bro.
 

Renfro

Well-Known Member
I think the point of calibration solution is that it's a standard for accuracy. I will skip the vinegar. Plus what meter calibrates at 2.4?
 
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