Harlequin Shrimp (Hymenocera picta) have become very popular within the saltwater aquarium hobby not only for their stunning colors and unusual behavior, but their ability to eradicate nuisance starfish, such as Asterina species, in the home reef. These shrimp have large, ornamental claws which are not used for hunting, but rather for putting on cryptic displays where they will wave these claws around. These shrimp do best when kept in pairs in aquariums with moderate lighting, and will typically hide in the shade during the day, emerging at night to hunt in groups. Unlike many other commonly kept shrimp species, Harlequin Shrimp are NOT scavengers and have very specific dietary requirements. The Harlequin Shrimp specifically feeds on the tube feet of echinoderms such as starfish and urchins, and in the absence of pest echinoderms, must be fed a constant diet of starfish legs from readily obtainable species such as the Chocolate Chip Starfish. Similar to many other invertebrates the Harlequin Shrimp does not tolerate copper, high levels of nitrates or parameter swings in an aquarium.