In captivity they eat flake foods, brine shrimp and finely minced high protien foods, and are generally very hardy. They prefer well established aquariums with rocks to hide amoung as they are territorial at times. The general rule is to stock them either singularly or in groups of three or more. If they are paired the dominant one will probaly harass the submissive one. There small size, docile nature and colorful appearence make them good canidates for small aquariums, invertebrate aquariums, or tanks with a mixture of docile species.
Lets look at the four families.
Family Opistognathidae Jawfishes are secretive fishes that frequently excavate burrows that they defend against all comers. Despite these displays they are harmless and should be placed with other docile species. They need a tank with lots of gravel to dig their burrows. They are finicky at first, so watch their food for the first few weeks. They are quite hardy and the 765 plus species show a variety of life styles.