I'm using pucks and the pH has been rock solid at 7.7 for 6+ weeks now. Almost to the point of I felt redundant testing it every evening or two...look at the color, yep 7.7 as always. TA was 100 but I haven't tested it in 3+ weeks so I "assumed" my TA was good because of pH stability.
With unusualy cooler temps (low 70s highs, low 50s low) I put my solar cover on for 24 hours for a pool party on Sunday. Sunday had high bather load most of the day, no trouble with FC or clarity. I tested FC at 7 and pH was 7.4. That got my attention as pH has been so rock stable. Off to check TA = 70.
So my TA was probably why my pH went down (pucks are acidic). Bumped TA to 110 with baking soda which also raised pH to 7.5 so I'm going to let it sit there and see what happens.
I guess my question is why the sudden drop? Bathers? Sun not being on pool because of cover? There are two things that changed, so I'm trying to understand better. Solar cover on, heaviest bather load of the season were the changes not to mention radically cooler temperatures.
Thanks in advance.
pH 7.7 -> 7.4 -> 7.5 (baking soda addition)
TA 70 -> 110 (baking soda)
FC = 6-7
I should have known something was up when opening my eyes underwater the water wasn't "perfect"