Black Cap Jawfish


Scientific Name: Opistognathus randalli
Family: Opistognathidae
Color: black, green, orange, tan

Fish Care

Fish Diet: Carnivore
Aggressiveness: Non-Aggressive
Reef Safe: Yes
Minimum Tank Size: 55 gal
Max Size: 4.5"
Relative Care: Moderate


Jawfish do well in reef tanks that have sandy bottoms. They like to dig tunnels and move sand around the tank. They live in these tunnels, with their heads sticking out, waiting for food to come by. When it does they will come out and grab it, then retreat back into their hole. They do well in pairs but some are aggressive and will fight with each other, especially the Blue Spotted Jawfish. They need tanks of at least 20 gallons with non-aggressive tankmates. Even though they live in tunnels for protection they need to come out to get food. If placed with aggressive fish, like dottybacks or damsels, they will either be chased from their tunnels or be too frightened to come out and get food, so care is needed when selecting tankmates. This is the largest of the group and gets to be a pretty good size, with its head getting very large.