On my LR I have some white fuzzy stuff. It lloks kind of like mold but white. It is about the size of a nickel. It is in two spots within about 3 inches of each other.
All of the fish are alive and the snails are the same. The only thing that could be missing is crabs. It isn't thick though. It is very very thin. I was thinking maybe it was some type of mushroom.
is there a hole in the center, q tip sponges look like white fuzz(or mold), adn are conical in shape with a hole in the center, often found in low light, ours are on the underside(shaded part) of the rock