Quote Originally Posted by Tredge
I have a heavy epoxy coating on the pool so the grout and plaster are protected.

I have my CYA at 40. I'm reluctant to follow instructions and bump it to 80
OK, thanks for the info. As for the CYA level in SWG pool systems, this is a matter of vigorous discussion at CYA for Salt Chlorinator Pools II in The China Shop. It appears that for most people, following the manufacturers recommended 70-80 ppm CYA level makes the salt cell run more efficiently (your manufacturer may have a different optimum level, but most are pretty high) probably due to the CYA taking away and tying up chlorine away from the generation plates of the cell. Otherwise, too much chlorine builds up near the plates and slows down the generation process. This means that at lower CYA levels you have to have your cell running at higher power and/or longer times in order to achieve the same FC level.

There isn't that much debate about this efficiency improvement with higher CYA. The main debate is over whether Ben's CYA table still needs to be applied -- do you have to have higher FC to prevent algae (disinfection levels still seem OK). Many people do OK, but some do not, so the jury is still out and it's a hotly debated topic. I'm just letting you know what's up -- you should obviously do whatever you feel comfortable with. It's too bad that it's not easy to lower CYA once you've raised it; otherwise, you could just experiment with this.

Richard