I have a Taylor K-2006 kit
FC = 8 to 12
PH = 7.6
TA = 80/90
CYA = 70 (This has dropped from the 90 to 100 range within 3 weeks of using the bleach in lieu of chlorine tabs)

It has rained pretty hard here over the last couple of days, so is it possible that I am getting a false CYA reading? If not, can evaporation and refilling with hose naturally deplete the CYA level this quickly? If the CYA level is correct, I was going to drop my FC down to 6 to 8.

Please advise.

Thanks!