Vinyl liner, ph 7.0, alkalinity 60, chlorine 8.0, I don't know what cya is or how to test for it. Anyways, every year, my alkalinity goes off the charts >240 and I can never get it back down...even hired someone and they couldn't do it either. Even tried some fountain methods...losing battle. My water here has high alkalinity and since I am vacuuming to waste 2X a day and replenishing the water, can I wait until I get the process of vacuuming to waste is over and then test my levels after all that new water is in and adjust or will killing off the algae not work unless it is adjusted? I've never had alkalinity anywhere near in the normal range, so starting this year off low has me a little excited that it might be normal for once, but I don't want to screw it up with raising now with all the new water that I know will raise it, but at the same time, it is pointless to not adjust now if I can't get rid of the algae. I think it is working as the pool started off black(okay, maybe dark dark green with about 5000 tadpoles and 200 frogs) and it is now a milky blue color after 3 days....woot. Also, any suggestions of how to keep alkalinity perfect once I get it there? Thanks.