(TF-Pro) Unable to calibrate the PH-009(I)A Pen PH Meter

[Gamebuster]

I just purchased a TF-Pro test kit.

I'm attempting to adjust the PH-009(I)A PH meter.

I added the entire packet of ph6.86 solution powder into 250ml of water at 25°C, and mixed until the powder was fully dissolved.

I then inserted the Pen PH Meter into the mixed solution up to the immersion level. The meter read a PH of 5.5

Using the provided screwdriver, I rotated the adjustment trimmer in both directions. The reading on the meter changes rapidly and randomly while the trimmer is being rotated. When I stop rotating, it returns to 5.5

When removed from the water, it reads a PH of 14, at all other times, the PH is 5.5 and does not change.

Is the meter defective? And should I even be using it, since the kit comes with the TF-Pro view tube and assorted chemicals?

 

[DrewLG]

Is the meter defective? And should I even be using it, since the kit comes with the TF-Pro view tube and assorted chemicals?

If you're colorblind, your best move is probably to purchase an $80-100 Apera meter with a case, calibration/storage fluid, etc. Otherwise, yes, I would just use the color-comparator test included with the TF-Pro; it's as fast as the meter you have, and it will be significantly more dependable.

 

[Britali]

I do not have the meter you have but I do have the Apera PH60 and I can tell you it is much easier to calibrate. It is all digital & comes with the 3 calibrating solutions (no mixing it yourself)…walks you step by step on how to calibrate it digitally for each.

 

[jesse-99]

I have the Apera PH60 too... Curious, do you calibrate ONLY the 7 and 10 solution? or do you calibrate the 4 as well?

My PH60 always seems to read higher than both my Taylor and TFP kits for pH. like .2 higher, even with calibration (all 3 levels). I stopped using cause I just feel better using the Taylor kit . The PH60 seems to come down and settle, way too slow for me, and just hasn't left me with a lot of confidence of late.

 

[Gamebuster]

I have the Apera PH60 too... Curious, do you calibrate ONLY the 7 and 10 solution? or do you calibrate the 4 as well?

My PH60 always seems to read higher than both my Taylor and TFP kits for pH. like .2 higher, even with calibration (all 3 levels). I stopped using cause I just feel better using the Taylor kit . The PH60 seems to come down and settle, way too slow for me, and just hasn't left me with a lot of confidence of late.

I was following the directions in the packaging. I only tried with the 6.8 solution, and did not try with the 4.x solution, as that was for a later step. No 10.x Solution came with the product. I'll probably throw the thing away, it looks like a piece of junk. I could probably make and program better one with an arduino if I really wanted to.

 

[Britali]

I have the Apera PH60 too... Curious, do you calibrate ONLY the 7 and 10 solution? or do you calibrate the 4 as well?

My PH60 always seems to read higher than both my Taylor and TFP kits for pH. like .2 higher, even with calibration (all 3 levels). I stopped using cause I just feel better using the Taylor kit . The PH60 seems to come down and settle, way too slow for me, and just hasn't left me with a lot of confidence of late.

I calibrated with all 3 and mine is .1 higher but consistently, so I figure that in. I ran both for awhile to see how consistent it was. Use the meter on my quick dailies (FC, CC & pH) and use the drops when I run my weekly full tests. I sit the meter in a small beaker of pool water (after swirling to get out air bubbles) at start of testing and then check after done with rest so not just staring at it lol.

 

[an1vrsy]

I have the Apera PH60 too... Curious, do you calibrate ONLY the 7 and 10 solution? or do you calibrate the 4 as well?

I also have the Apera PH60. IIRC, the documentation instructions specifically state that if you’re only calibrating with 2 solutions, then use the 7 and 4 solutions.