Ladies and gentlemen:
I am two weeks past a successful AA treatment to lift staining from a vinyl liner. I am now getting test results that are basically not measuring any CYA, when I was high all last year. In the middle of last season, CYA was 100 and I had to partial drain to get it down to around 75. I wasn't really testing CYA this spring, assuming it wasn't moving. Now after AA treatment, I am having difficulty keeping any FC levels at all, and am not registering CYA with my test kit. Can the AA treatment directly affect CYA, or can the CYA deplete on its own, or should I look at replacing my reagent?