Quote Originally Posted by waterbear
With a cartridge filter and trichlor it can only be a matter of months before the cya is way too high. I have personally seen these trends in the testing histories of the customers at the pool store I work at.
That's good information to know. My husband used to use trichlor a lot during our first pool season (2 years ago). I found some old printouts from the pool store the other day, and our CYA was ALWAYS high...like around 90-100ppm.