Our bicolor blenny has been very hearty and personable; entertaining to watch, not at all shy, and has a very healthy appetite. Gets along with everyone in the tank, with a couple of wrestling matches for dominance between him and our lawnmower blenny. Hasn't bothered corals that I've noticed, except when he decides to perch on something and momentarily irritates it. Does graze on the algae on rocks, which includes the coraline kind.