What do you think? I thought it was a slug at first because I can't really tell if there's a shell, but after some research I'm hoping it's a stomatella snail.
amazing algae eaters, I am guessing they don't breed them for aquariums because that would kill the industry. They polish everything. I had a big population until my filefish discovered they were tasty. I got rid of him. I hope they come back. All you need is one and patience.