Monday morning rant...It just seem like it would be easy to add CYA when needed...Why don't they make a "just chlorine" puck. I spent the money for the Rainbow 320 Chlorinator and by using it, the CYA levels end up well over 100-150 in no time at all. (rant....It seems a little like a scam to keep us using more and more chlorine)! So, why not make it without CYA? When I went over 200 cya, I asked the pool store owner about it and he said, "don't worry till it's around 3-400!!! No joke!.