We started up our pool last week with a clean fill of water from the mains (pH about 7.5), and the water is nice and clear. But the pH has been over 7.8 for the past three days since I added cal hypo, and doesn't seem to be coming down. We use trichlor tablets in an erosion feeder to chlorinate the pool, which ought to bring down pH. I've also used about 2 kg of dry acid in total added around the edge of the pool (not all at once, but over three days). Should I just keep going with the dry acid, or is something else going on? Probably I'm just being daft, but we had problems with constantly rising pH last year and it worries me.
Test results this morning:
CH= 280 (guessing based on fill water, will test properly next time)
CYA=14 (calculated from amount of dichlor and trichlor used)