PH does not want to go down below 7.4 when adding Muriatic acid..

[zrtman]

Just somewhat puzzled or curious about this. I know 7.4 is a good number...

When I filled pool on 6/11 had TA 150 and PH 7.3. Followed the advice on here and did not add muriatic acid until PH was 8.

PH was 8 on 7/7. Using the app/pool math 16oz of 34% Muriatic acid would bring me from 8 to 7.0. So I did half first (8oz) then tested it after an hour - PH was 7.6 - pretty much spot on. So I added the other 8 oz and waited an hour. It went from 7.6 to maybe 7.5.

So I wanted a day - checked again, PH was still 7.5. Added 12 oz of Muriatic this time - checked gain - it is maybe 7.4 - more like still 7.5.

I have not filled pool. The water temp is high @94 by late afternoon. CH 250, Salt 3000, CYA 60, FC 4-5, CC 0.0. TA has dropped from 160 to 125.

Was planning on just leaving it alone for now and letting it drift back up to 8 before adding more acid. Just curious as to why it moved down from 8 quickly but being stubborn to go below 7.5ish on PH. Was trying to drop to 7 to help lower my TA to 80/90 (high side of recommended level).

Any thoughts as to why it is stubborn let me know thank you.

 

[ajw22]

Your pH is stubborn due to your high TA.

Adding more acid will force the pH lower.

I would not worry much about your TA. Lower your pH around 7.4 and your TA will come down over time.

 

[zrtman]

Your pH is stubborn due to your high TA.

Adding more acid will force the pH lower.

I would not worry much about your TA. Lower your pH around 7.4 and your TA will come down over time.

Ok great thanks! That is what I figured.. just wanted to double check I did not have anything wrong.