Almost, but not quite balanced...pH and alkalinity driving me crazy

[WEpool]

Have had our 1700 gallon fiberglass INDOOR swim spa operational about 6 months. I use a liquid based test kit and chlorine bleach from home depot (HDX) to sanitize.

I am getting weary of a never ending constant need to adjust the pH and alkalinity. Last readings were pH 7.8 and TA 60. Usually, I get readings like this and try to raise the TA, and then lower the pH. Of course, once I raise the TA, pH is higher and then I add a pH reducer and then the TA is too low again. Seems the two readings are always a problem.

I have not had a problem keeping our free chlorine levels from 1 to 3 and have low levels (0.2 or less) of combined chlorine. Our Ca level is 175.

I thought over time, it would become more straightforward/routine. This is not happening...any suggestions?? Would raising the CA level even higher help?

 

[ajw22]

Welcome to TFP.

TA of 60, even 50 is fine. Any pH in the 7's is fine. Stop adding chemicals and yoy-yoing the TA and pH.

What test kit are you using?

What is the pH and TA of your fill water? Do you have an autofill on the pool?

Please create your signature with details of your pool. It helps us help you better.

 

[YippeeSkippy]

Calcium in a acrylic/fiberglass spa/hot tub (spool too, maybe?) is mostly to control foaming. I see no value in increasing it.

All the jets in a spa encourage the pH to rise. A tablespoon or two of Muriatic Acid will help when your testing shows a need. As Allen said above, relax about the TA being 60.

Maddie

 

[WEpool]

Welcome to TFP.

TA of 60, even 50 is fine. Any pH in the 7's is fine. Stop adding chemicals and yoy-yoing the TA and pH.

What test kit are you using?

What is the pH and TA of your fill water? Do you have an autofill on the pool?

Please create your signature with details of your pool. It helps us help you better.

Fill water testing today was pH 7.4, TA-110. It is community water.
Taylor K-2006 (FAS-DPD chlorine test)
Pool info added to signature.

This am pool water-pH 7.6, TA-50, TC-3 ppm. Based on your comment...leaving it there for now!
Thanks.

 

[WEpool]

Fill water testing today was pH 7.4, TA-110. It is community water.
Taylor K-2006 (FAS-DPD chlorine test)
Pool info added to signature.

This am pool water-pH 7.6, TA-50, TC-3 ppm. Based on your comment...leaving it there for now!
Thanks.

Forgot to add, no we do not have an autofill. The sunroom where pool is has a "washer" hookup in the wall for us to use to fill. Pool cover is an end2end brand and pool stays covered when not in use.

 

[ajw22]

With fill water TA of 100+ the pool TA 50 will naturally rise as you need to add water.

 

[WEpool]

Thanks, Allen! We don't need to fill very often or with very much (maybe an inch once a month).

Pool is about 48" deep; I added about an inch fill yesterday.

Testing today- first free Cl test was 1.6. I added 3 oz bleach; testing 2 hours later with jets on...

free Cl...3.8; ph 7.8 and TA- about 45? (color started turn at 40 and complete at 50).

I elected to leave this alone although TA clearly on low side; if I bring TA up any would need to bring pH down slightly. Would be back to the yo yo?

 

[ajw22]

TA of 50 is fine. Test endpoint is when you get no further color change, not when started to turn.

As long as your pH is staying at the high end of the range then your TA is not an issue.