Looks like a Vermetid snail. When you feed the tank, do you see a long "fishing line" coming out of it?
If so, the easiest way to deal with it is to fill the tube with superglue.
Looks like a Vermetid snail. When you feed the tank, do you see a long "fishing line" coming out of it?
If so, the easiest way to deal with it is to fill the tube with superglue.