Premnas Biaculeatus

Question
At work, we have a 75 gal salt water tank.  We have a clown fish that has been behaving oddly since a little before Christmas.  It's about 3 - 4 years old, about 3 inches long.  There is no mate, and no anemone in the tank.  It floats down to the bottom and lays on its side.  Could he be sick? The guy that takes care of it regularly tests the water and said all is fine in that area.

Answer
Sometimes clowns, including your maroon exhibit this behavior. If he he is, for the most part active and eating well, he is probably fine. Premnas act differently when wild caught as opposed to being tank bred. Sounds like a male due to his small size. Females are double the size of a male. Although there are many clown types, premnas is the only member of its genus [monotypic], biaculeatus refetrs to the spines on its gill covers, thus the name "spine-cheeked clownfish".Keep me informed of his behavior. Gerry.