I'm following the trouble-free pool formula for success and I have a few questions.
1. My CYA is a normal range but went down about from 50 to 45. I thought the only way To decrease cya was water exchange?
2. My pH recently went up from 7.6 to 8 what causes the pH to increase? I did add acid according to the pool math calculator to bring the pH back down.
3. What is combined chlorine and what causes it to accumulate?
Thanks you guys have been great!