I recently re-filled my hot tub and I’m getting a new brown staining on the built in Frog system (pictured). I also have some brown / scum stains around the edges I use the Frog system minerals and chlorine. When I filed my hot tub I used metal gon and have continued to use defender. Along with Enzymes and Bright & Clear. Levels check out good, chlorine is a little high right now. I also have a scum ball that started out white and turned pretty brown within a couple days. What am I missing? Any other chemical recommendations? Thanks in advance.
