Many pools have a pH at which they like to "settle"--my pool wants to stay at 7.8 no matter what I do or how many splashing kids I have in it...I spent the first few years fighting it with acid to get back down to 7.4 or so, adjusting alk, etc. and finally just realized that if I left it alone, it would stay at 7.8. (My fill water is 7.8).Been there now for the last 4 or 5 years with no help from me. So....don't panic, just test every day or so to see if it stops at 7.8 or if it keeps rising. If it does,, then you can lower it with acid. If it doesn't, then you can relax and not worry about it.

Janet