The Fiddler Crab is a hardy species that does well under proper living conditions. The Fiddler Crab originates from the brackish, inter-tidal mud flats, lagoons, and swamps of Florida. As such, the Fiddler Crab requires some salt in the water in order for it to thrive. In addition, contrary to popular belief, the Fiddler Crab is not a fully aquatic species.
The Fiddler Crab is a semi-aquatic species that requires access to an area above the waterline. A "beach" or "shoreline" made with sandy substrate is ideal. The use of aragonite substrate will help maintain higher pH levels and provide a source of calcium and important trace minerals. The Fiddler Crab aquarium habitat should be aquascaped liberally with rocks, driftwood, and other decorations to offer hiding places and climbing areas. However, be sure to leave an open area for burrowing and digging. Good water quality is important for the health of the Fiddler Crab. An internal filter is a great way to provide both proper filtration and water movement for the Fiddler Crab habitat. The Fiddler Crab is a capable escape artist so a tight-fitting cover is essential.
The Fiddler Crab is extremely interesting to watch especially when it is actively searching for food or when the male Fiddler Crabs are trying to attract a mate. The male has a large brightly colored claw it uses to "call" or signal females. The female Fiddler Crab has two small claws.
The Fiddler Crab is an omnivore that will eat commercially prepared flaked foods and algae as well as freeze-dried bloodworms and brine shrimp.