I resurrected our swampy pool at the start of summer and had a nice clear pool for 2 months, while maintaining pH at 7.5-7.8 and FC 4-7. Now, two weeks ago, nearly overnight, I'm back to swampy green, can't see to the bottom at all. I don't know what else to do. Below are the values been maintaining round the clock for at least a week or more with no change. No chlorine loss overnight or really much during the day either. HELP!
FC: 16 or higher
pH: 6.8 (had to lower it because it had gotten high and I read here that chlorine not effective at high pH; not to mention that the algae blooms raise the pH)