Electronic PH Testers

revitup

Active member
Nov 30, 2019
25
Pawleys Island, SC
I had no confidence in my ability to accurately test for PH using the Taylor color block test. Am now using a Apera Instruments PH60 tester. Love the accuracy and no-nonsense digital readout. I calibrate it about once a week but that's seeming like overkill, it hasn't ever been off more than .02. I've seen where PH tests are inaccurate with FC levels higher than 10. Does this apply to just the Taylor color block test and similar, or does that apply to the electronic testers like the one I'm using also?
 

Rattus Suffocatus

Silver Supporter
Jun 5, 2019
447
Corona de Tucson, AZ
You could always run a little bit of an experiment and try it with your meter. Grab a gallon of water and some bleach and have at it.

So far my electronic meter seems to be less sensitive to chlorine levels but I never really have pushed it. I am using a cheap Chinese meter, which is fine as long as you calibrate it every time you use it. Maybe I need to invest in a better one. Weekly would be nice. I generally am doing titration tests except on weekends now because I don't have the time to calibrate it daily..
 

Alset2

Gold Supporter
Aug 16, 2019
50
Cent Fl
I use the Extech PH100 . I am presently collecting data via testing twice a week with same water sample and tracking results.
FWIW - I have found, so far, that the PH meter is fairly close to the TF color block testing . However, last 2 weeks the meter has been about .1 lower than what I come up with on the color block( all subjectivity duly noted) . But I consider that acceptable for a PH reading . My meter supposedly accounts for water temp too .
One thing to note is that my FC level has been steady at 10.5 for that same amount of time, But I thought that would make my color block reading lower if anything?

I hope I am not intruding, I am just very interested in this stuff...
 

revitup

Active member
Nov 30, 2019
25
Pawleys Island, SC
From what I understand, a FC level of 10.5 would not be significant as far as invalidating the color block test. It isn't that far above the "10.0 limit". As you go higher above that limit though, the color block test would result in a more purple color than red leading one to believe that the PH level is somewhere north of 8.0 when it may not be.
I was always thinking I was seeing a more purple color when my PH rose into the upper 7's even when I knew my FC was below 10. That was one of the things that pushed me to get the Apera device. That, and I just like gadgets!