Crab – Box

Box Crab Care Tips:

Minimum Tank Size:  20 Gallons

Max Size: Up to 15cm (6″)

Diet: Carnivore

Temperament:  Semi-Aggressive

Lifespan: Unknown

Scientific Name: Calappa Hepatica

Coral Safe: Yes

Invertebrate Safe: No

The box crab is a predatory and rare species that is occasionally seen in the hobby. Their scientific name is Calappa Hepatica but they are referred to as the box crab, the red spotted box crab (due to variation in colour), or the smooth box crab. These crabs are a part of the Calappidae family. These crabs can reach a maximum body size of 6” wide, due to their rarity seen in the hobby, their lifespan is currently unknown. Box crabs are carnivores, their claws are shaped specifically for grabbing snail shells and cracking them open. The snail shell will be grabbed with one arm while the other, stronger arm, will slowly cut pieces of the shell off until there is a large enough opening to grab the snail meat. They will eat other types of meaty food if snails are not present, they can be supplemented with any chunks of meaty food, or silversides. They should be fed every second day if larger chunks of food are given, if only small pieces are given, they should be fed everyday. Box crabs will often sit still on the sand/glass, they do not require a large size tank due to their activity level and therefore have a minimum tank size of 20 gallons. Box crabs are semi-aggressive and should not be kept with any small or medium sized fish. Species specific tanks are recommended but they can also be kept with large fish, as long as the fish do not sleep in the rocks or the sand. Keeping them fed regularly will help lower aggression levels. Box crabs do not climb rocks very well and will often be seen on the bottom of the tank, they also have a very heavy body compared to their legs and may need help standing upright if they fall onto their back.