Hi...my first post, thanking responses in advance.
From Taylor kit test my CYA level doesn't even come close to 100 mark which, since scale is inverted, I'm assuming it means it's around 200 or so. Tested twice, same result. From what I've read here the only way to lower this is to drain and refill. Question is, how much to drain? I know the answer will probably be 'it depends' but for a ballpark, is that 1/10 of the pool, 1/4, etc.
Other test results show pool needs some chemicals (need to raise ph, etc.) but if I'm going to be draining/refilling, doesn't make sense to try to work on other stuff until I get CYA under control because I would be losing new chemicals anyway, correct?