Sandy,

I have an Aqualogic controller with SWCG. Last month my CYA was 30 ppm with chlorine at 2 ppm with no difficulties. However, as Pat and others maintain, higher CYA improves chlorine production so I decided to raise mine just to see if it was true.

First I raised it to 50 ppm but I did not see any rise in my residual chlorine, still 2 ppm. Then I raised it to 70 ppm and I still did not see a rise in my residual chlorine, still 2 ppm. However, during this time, I did not have a heavy bather load so I am not sure if that would have made a difference or not. So for me, running at a higher CYA did not improve chlorine production and I cannot see any other benefit from doing so.

Anyway, I told this story so perhaps it might help in your decision. Just remember, it is much easier to raise CYA then lower it.