In January of this year I noticed several small (1-1/2” long) rust colored stains at the bottom of my gunite pool. It was finally warm enough this week for me to dive down to inspect them. I unsuccessfully attempted to remove them w/ a wire brush. They appear to me to be rust stains, although I never found the culprit (nail, screw, etc.).
Does anyone have any suggestions as to how they can be removed?
24,500 Gal Underground Gunite
rectangle 11.5K gal IG concrete pool;; 125sf cartridge filter; 2hp 1 speed pump; K-2006, k-1766; PF:10