What does a Sea Urchin look like when he's eating?

Our tank was getting a little too much algae, and the snails were exhausted, not to mention full, so we got this little guy, and I have to tell you, he not only eats the algae, but the rock is cleaner than when we purchased it! He's wiping out the coralline algae which is a shame, but he moves so slow it will probably grow back by the time he gets back to where he started.

Unfortunately when we bought him, we didn't see that he had a ouchy. This is actually the bare skeleton (called the "test") showing where the epidermis is gone. This would be the equivalent of have some skin missing from your head and your skull showing through. Hopefully it will heal and not become infected (if it's not already).

Open Wide

Close up of mouth with teeth retracted show what could be considered a tongue