Pool owner 32 years and this our first time fighting high CYA numbers. We have used tablets all these years and have never had this issue before and don’t understand why now.
Welcome to TFP! In your area with a relatively short swimming season, coupled with good water exchanges each winter/spring, some pool owners are able to use tabs (pucks) more than others. But overuse of tabs without water exchange increases the CYA too high, then the free chlorine (FC level can't keep-up as noted on the FC/CYA Levels. That's why we recommend liquid chlorine or regular bleach as your primary sanitizer. It would be ideal if you posted a full set of test results from your TF-100 (link below) or Taylor K-2006C test kit. In addition, update your signature so we can help you better,.
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