I had a female for a few years, during which time she grew from very very small to close to her adult size. I had almost no problems with her, although I did not tempt her much. Upon being put into the tank she pretty much desimated the hitchhiker feather dusters that were on my live rock (but I think she was just hungry, because later she showed no interest in the few that lived.) She occassionally picked at a snail or two, but most learned to press up against whatever they were grazing on as she swam by (and I never saw her actually get a snail off a rock -- but she would nip at them if they were exposed.) Similarly, she seemed to enjoy going after hermit crabs, but I don't believe she ever ate one. I had a mature cleaner shrimp, a serpent star and a brittle star (both of whom had cover under rocks), and some gorgonians and soft corals that the toby never bothered. I also had a pencil urchin that went about its business (eating my corals) without ever being bothered. I really loved that little toby -- she was a very interesting fish and I wouldn't hesitate to get another one.