jaymac10

Newbie HT user here. I have this coating on the knobs as well as in certain parts of the tub itself typically right around the water line. It also seems to be building up on the cover. 8 person hot tub with ozone. All I really use is a capful of chlorine shock granules after each use. When I check my chemistry, the only thing that I can never get into the "normal" or optimal zone is the Free chorine. But most others are within normal range. Thanks for the help! Jay