The Decorator Crab is a member of the Majidae family of spider and decorator crabs. It decorates its brown body with sponges, shells, rocks, and other items as a method of camouflage.
They are nocturnal, hunting at night. In the reef aquarium, it harvests algae, soft corals, and invertebrates to adorn its shell. This activity may cause harm to some soft corals, but in the large reef aquarium, this activity actually helps spread and propagate these same corals throughout the aquarium.
The diet of the Decorator Crab should include chopped meaty foods such as fish and clams.