Confusion on pH testing methods from long-time pool owner

[cehmtx]

Owner of pool since 1986. TFP member and user since 2013. Still confused about pH testing. (Chlorine bleach used as sanitizer.)
I now use three testing kits.
Primary test kit since 2013 is TFP-100. But no pH test.
Primary test kit for pH is K-1000.
Secondary test kit for Cl, pH, & TA is Bioguard Multi-Test 1200-V.

K-1000 pH test range is 6.8 to 8.2 but in fairly wide intervals of 6.8, 7.2, 7.5, 7.8 and 8.2 by color matching or interpolation of color matching.

Bioguard pH test range is 6.8 to 8.2 but in fairly wide intervals of 6.8, 7.2, 7.4, 7.6, 7.8 and 8.2 by color matching or interpolation of color matching.

In 1986 (when began a pool life), pH "ideal" range for vinyl liner pool was 7.6 (range 7.4 - 7.8).

In 2013 when I became a TFP member, the recommended pH range was 7.2 - 7.6.

Since TFP membership in 2013, I have noticed that recommended TA range has dropped to 50- 90(+) (from 100 - 120) and pH range is now 7.2 - 7.8.

After pool season last fall (2016) I purchased a pH meter model PH-009(I) pen type for greater accuracy in pH measurements.

I have NOT yet used it since I was SLAMMING pool so far in 2017 and it is still covered (but clean and clear) as of today, but at 67 deg F.

Since the PH-009(I) pen testing procedure is dependent on temperature and uses exhaustible chemicals, and must be calibrated to achieve accurate results, is pH ACCURATE testing really necessary?

If so, I believe I will need more expendable chemicals for testing for the PH-009(I) of the pH buffer powders at pH 6.86 @ 25 deg C and pH 4.01 @ 25 deg C during the 2017 season (May - early Sept.)

--OR--

Are the two test kits I have (K-1000 and Bioguard Multi-Test 1200-V) adequate for achieving reasonable pH results for use with the accurate free Cl and TA testing with TFP-100?

Thank you.

 

[jblizzle]

I think you might be over thinking this a bit. It is generally just necessary to keep the pH in the 7s ... trying to be too accurate is just going to drive you nuts. We also generally do not trust the digital testers as then need constant calibration and there is no way to tell if they are giving you good results.

Your TF-100 should have come with the K-1000 test kit, so not sure why you are saying they are separate.
I would just throw the Bioguard test away and stick with the Taylor ... no reason to keep trying to get multiple tests to match.

 

[Richard320]

I don't have a problem with the K1000 test block. By squinting until it gets sort of fuzzy and holding it at arm's length, I can usually tell if the color matches one of the standards or if it's closer to one than the other. And the way they're spaced, that gets me to with .1, which is good enough.

The recommended ranges have slowly shifted over time through experience. A lot of people were constantly chasing the pH and TA around, but by allowing the TA to drop a bit lower, pH held steady. It's whatever works for you. If you find a spot where the pH holds steady for weeks, and it is within the safe-to-swim range, don't mess it up!