Description: Hermit crabs(though not “true” crabs”) are crustaceans. They belong to the infraorder Anomura. There are both terrestrial and aquatic species of hermits.

Shells: Hermit crabs use shells left behind by other animals such as snails and conchs for protection. As they grow they must find new shells to make their homes.

Feeding: They are scavengers and feed on a very large variety of foods of both vegetable and meaty matter. In an aquarium well stocked with fish it is usually not necessary to add additional food specifically for the hermits.

Identification: It is very difficult to identify hermit crabs to species. Hobbyists often refer to hermit crabs as “red legs”, or “blue legs”. As a consequence to naming these animals by colors hobbyist are sometimes sold hermits that are known to do harm to corals or even eat fish, as opposed to the “red legs” that are mostly reef safe. Use caution when buying animals online site unseen.

Special Notes: Do not be alarmed if you see what appears to be the lifeless body of a hermit inside the aquarium. Like many other crustaceans hermit crabs will moult their exoskeleton in order to grow and regrow limbs. Lobsters, blue crabs, and shrimp will also moult.

Sources:
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