I have a question concerning my yellow tang. I have a 75 gal FOWLR setup, and have had my first fish in the system for about one week. I have a yellow tang, four blue-green reef chromis, and two tank-bred percula clowns. All are doing great, and eating well. I have been observing them closely, with attention to the tang. Tonight I noticed him presenting himself to the chromis. He would approach and turn sideways and cant his body to give a full side to the chromis, extending all fins. I believe he was looking for a good grooming, but I see no evidence of parasites, ich, or velvet on him. He is not aggressive, and when they do not acknowledge him he swims awhile, then presents to another chromis. Is the tang developing parasites, or is this expected behavior?