i have two in my 120, they've been in there from the beginning. they don't cause much trouble, but i suspect they're the reason i've never been able to keep a school of chromis. they do bite when i get near they're barnacle that they lay eggs in regularly(free coral food!), and they have their own ideas about decorating near the barnacle too. if i set anything new nearby the male will move it away. i've seen him pick up some surprisingly big rocks, it took me awhile to figure out how this was happening. then i saw him in action, i'd been blaming the hermits.
abe
60G cube, now planted amazon tank