has our hippo tang lost his mind?
 

we had read hippos were grazers and helped a lot with various greens in the tank. we purchased a young one, and he's doing great, but he won't pick at the rockwork at all. he eats flakes like crazy and thinks he's a clown (as in hangs right by them and swims around with them). has he lost his mind? could his flake diet create any problems? they're supposed to be herbivores but he loves the flakes. :confused: