jonboyb
Aquarium Advice Activist
Moved some rock around in my tank and found several of these on the rock. They do move, but very, very slowly and they seem to just rotate around instead of being truly mobile. I have about 6 of them with a max size of maybe 1/4". I have poked at them and they appear to be hard. They have a "funnel" shape to them. Tank has been running around 3 months now.
