Is there an ideal cyanuric acid level?

[JimK]

CYA of 40-50 is the general recommendation for manually dosed pools. For SWCG pools, the recommendations you'll find here are to run CYA at the top of the SWCG manufacturer's suggested range to reduce the load on the cell and extend it's life. You do need to keep your FC at the appropriate level for the CYA level you have.

Yes, it has to do with the chemistry at the electrodes, as well as the issue BigDave mentioned. I think it's been covered in the China Shop by Chem_Geek, but I don't have time to go poking around for it right now.

But, your cells will last longer that the higher level, since cell life is proportional to ON-time, and they'll be on less at the higher CYA, even with the higher required chlorine levels. Read through the Best Guess page, linked in my sig, for more info.

Thanks.