Quote Originally Posted by chem geek View Post
Yes, the cloudy weather cut down the amount of UV so less loss of chlorine. And yes, for a given CYA level a higher FC level will lose more absolute FC because the loss is roughly a percentage loss so the same percentage of a higher number is a larger number. A target of 5 ppm is fine with 80 ppm CYA. 4 ppm would be an absolute minimum with 80 ppm CYA for a pool with a saltwater chlorine generator.
Thanks.