Pros: Eats uneaten food, attractive look
Cons: May eat fish and inverts, such as damselfish and hermit crabs, may eat food not intended for it
The arrow somewhat resembles a spider, with long brown stiped legs, and claws with tips dipped purple or blue. They are called 'arrow crabs' due to the shape of their mantle, which is shaped like an arrowhead. Although attractive, they can be very destructive. They are diurnal and nocturnal, and will often prey on small, resting fish. They are also know to pull hermit crabs and snails out of shells, even large ones, such as electric blue hermits. They are nice additions to reef tanks that do not have many hermits and snails, or small fish, for they do not consume corals. Care should be taken when keeping an arrow crab.