I used to try to keep my CYA in the 20-40 range when I was running a chlorinator. Seemed to work pretty good over all. Now i have a SWG and the range is 80-100. I keep mine around 80, but still seems top require a high CL reading to keep algae at bay. Is there some intrinsic reason that a SWG requires a much higher CYA level? Since my MFG recommends this level, I have tried it, but am not that happy with it. But I don't want to cause early cell wear or anything.