Hot Tub Scum Absorber Whale - 2 Pack Oil Absorbing Hot Tub Floating Sponge Cleaner Absorber, Keeps Water Clear, Reusable Pool Scum Absorber Hot Tub Spa Accessories

We worked through the same thing. Even though it looks clear and you filtered it, there were still minerals. It is part of the process. I got these and you can wipe off the scum very easy: https://a.co/d/0d8VExCc