He is mainly a nocturnal crab and only becomes active when the lights go off, I have moonlights on my tank thank goodness or I would probably never see him. But he is neat when comes out, he is very shy and doesnt really want any part of anything else in the tank, he mainly catches food out of the water column and mops up detritus off the sand with his anemone's. They are reef safe with no worries, This and a porcelian crab would be the only crabs I ever stick in a tank.
Oh I have had him for 8 months now, he came as a hitchiker, which was great as I had intended to keep one.