Taylor testing result and local pool-store testing result differ a lot

[bfang711]

hi guys,

Since last season, I started testing my pool using Taylor. However currently right before I try to close my pool, I found out the result from Taylor kit differs a lot with what the pool-store tested. (It used to match pretty good.)

The reagent is R-0004 for PH testing. (The reagent is 1 1/2 years old. however I always kept it in the basement.) The result from R-0004 is 7.4. but the pool store gives me 6.8.

btw, The pool store makes my pool trichlor pool, however I just updated to salt pool at the beginning of the season. I don't think this can cause the big difference though, especially in PH result.

Has anyone met this situation before? How should I do now? should I listen to what the pool store guy told me to add PH+?

thank you.

 

[jblizzle]

Simplest solution is to stop letting the pool store test your water

Trust your test kit.

Trichlor is acidic and will tend to lower the pH, while a SWG tends to raise the pH.

 

[tucsontico]

If your testing with the Taylor kit (Which Taylor kit?) has been tracking similar results all season, I suspect the pool $tore is wrong. Generally, a pool using an SWG for sanitizing will have a rise in pH versus a drop in pH. I would not add pH+ until you test again yourself.

BTW, you signature shows a Pentair 320 Chlorine feeder but you say you're using an SWG. Which type of automated chlorination are you really using?

 

[bfang711]

Sorry, I just modified my signature to SWG. I changed to SWG in this season and forgot to update my profile. Plus I replace the old Vinyl liner with a new one at the beginning of the season. I will modify the signature.