Hello all! First of all, thanks to all on this forum who have educated me on pool water chemistry after I learned the costly lesson (taking pool store advice) that lots of others have learned. There is a wealth of information here and it has helped me catch extremely high CYA levels.
My wife Michelle and I (Greg) purchased our home in March of this year which included a 28K inground liner pool. We opened in early May and watched carefully as the pool guy dumped bottles of liquids and pounds of powder (what turned out to be tri-chlor and di-chlor) into the pool. The previous owners commented on how they never did anything except keep the tablets in the chlorinator and run the Polaris to clean. No bid deal at all, just swim and enjoy.
After reading about the negative effects of using only tablets, I ventured out to understand pool chemistry myself and not to count on the never consistent advice of a pool store clerk. Bought the Taylor FAS-DPD test kit and found myself collecting a wealth of information that I KNEW to be correct. All numbers were perfect with the exception of one....CYA. It read well over 100 on the first test, so I diluted the sample by 50% and ran the test again seeing a 90 as the result. Crud, my suspicions were proven. Just drained the pool down about 8" today and refilled after pulling every last speck of tablet out of the chlorinator. I switched over to liquid Cl and will monitor FC and adjust daily or even twice a day until I get a good feel for the chlorine demand.
Thanks again to all of you experts and we look forward to continuing our pool "education" with all of you!