After a calm pool season we now have a new problem. I test every day and results have been good. Today all of a sudden The PH is off the charts and the Ta regesters about 130. No chems have been added in the last two days other than the 3 inch pucks in two skimmers. I regularly add 10 minutes of water 3 times a day (I tested this too, PH was 6.8). I do keep the chlorine up by adding liquid 12% on occasion. The water appears slighly cloudy but not terribly. Pump pressure is good and stable. As an aside, the weather has been hot and humid the last three days. How can this happen and what do I do about it? I read the pool school chapter but to me the cause is unclear. Do I start pouring acid in the pool?