Bicolor Pseudochromis "Royal Dottyback" are generally reef safe. They will prey on your bristle worms, and can pick on smaller fish. Prefer water between 72-78 degrees. They get close to 3" long.
They are beautiful fish but can be very aggressive, if you are going to add one be sure there are no other fish with similar coloring or shape and add it as your last fish.
The one with the purple stripe beware they do go after bristtle worms but also go after other fish and are known as shrimp hunters,had one of those and it did go after shrimp,fish and not once went for the worms in the tank.
Yeah i hand one of those at my house(bicolor Pseudochromis), we dont speak of him anymore we called him the "evil fish" he didn't bother my shirmp until they molted then he whent wild and killed all my peppermint shrimp (cought him in the act) took him back to the LFS and said good bye to that little nightmare:nervous:
They have a similar color pattern. However the fins of a the bicolor pseudochromis are pale while the fins of the royal gramma are colored and it has the black spot. The royal gramma has a much nicer disposition.