I've only h :'(ad my tub filled for about 3 weeks. When I added sanitizer to the floater, I noticed a brownish tint on the floater screen. I took the screen off and inverted it. I went to add sanitizer again and the brownish tint is on the screen again. It rinses out but I'd like to know why this is happening what it is and how to prevent it.
All chemical readings are o.k.