Found in nearly all marine environments, Crabs can range from less than an inch to over 12 inches in diameter. This wide range of invertebrates can vary in size from small to very large. Because of their tiny size, these hermit crabs can really get into those small spaces in a reef tank that other hermits cannot. It is highly likely that if you live in the United States, you have one or both of these two species of crabs. This is by far the most common type of Hermit Crab on the market today. Finally, unlike some hermit crabs, most Scarlet Reef Hermit Crabs are very peaceful towards their tankmates. Small hermit crabs of the Genus Calcinus found in Hawaii are extremely efficient little critters. Crabs are scavengers of any type of edible matter they find, providing an invaluable "cleaner" function, consuming both undesirable algae and detritus while mixing the sand. Hermit crabs spend most of their lives living in shells but, unlike snails, they do not grow a shell of their own. Coenobita rugosus. 1. They also prefer some kind of … Purple Pincher Hermit Crab (Caribbean hermit crab) Caribbean hermit crab. The exotics are imported to the United States from the Pacific Rim. The back half of a hermit crab is soft and very vulnerable to predators. However, if you purchased your hermit crab from a mall kiosk or a Petco, there is a chance that you could have what is called an "exotic breed" of hermit crab. Hermit crabs can be found in many habitats, on land, on shorelines and in deeper waters. If you want to get hermit crab for your tank, there are a few hermit crabs you can consider. Hermit crabs are a type of decapod crustacean belonging to the superfamily Paguroidea. As hermit crabs grow, they have to discard their shells and look for larger ones. Some remain very small, only 1-1.5 cm in size, while other species in this group reach a length of fewer than two inches. Because of their tiny size, these hermit crabs can really get into those small spaces in a reef tank that other hermits cannot. Some Crabs, however, can be more aggressive, so it is best to allow them plenty of space and extra food when needed. The Scarlet Reef Crab … Just as there are many types of hermit crabs that can be kept as pets, so too are there many different breeds which can be kept in aquariums. For this reason, they resort to the corpse of another species, but they do not take advantage of it as carrion, but to inhabit it. More importantly, however, these small hermit crabs have a voracious appetite for detritus and algae. Try to provide around 1-2 pounds of rock per gallon. Crabs are remarkable scavengers that are constantly removing algae and debris tucked deeply into coral reefs and rock reefs. Their soft curved bodies can retract into hard shells left behind by various types of snails. What Types of Hermit Crabs Should Be Placed in a Saltwater Aquariums. Saltwater hermit crabs love to climb on rocks so make sure to put some rock in your aquarium. Hermit crabs use snails´ shells or other mollusks to cover their bodies, which unlike other crabs is soft and does not harden. Knowing whether your hermit crab can go in freshwater depends on what type he is. This does not matter because hermit crabs are clever enough to use a tough ready-made shell to protect the softer parts. Some remain very small, only 1-1.5 cm in size, while other species in this group reach a length of fewer than two inches. Though they are called crabs, they are actually more closely related to lobsters than true crabs. 6 Types of Hermit Crabs. From hermits, stone crabs, porcelains, sally light foot, anemone crabs, mithrax to name a few. They do well in any environment and are generally peaceful. Native to the reef faces and coral rubble of the Caribbean, these active scavengers can consume large amounts of animal matter and algae. Small hermit crabs of the Genus Calcinus found in Hawaii are extremely efficient little critters. Hermit crabs have been popular pets for adults and children alike for many years, and there are many who appreciate their unique beauty (and just as many do not-it’s a matter of taste). Another species of hermit crabs, the Coenobita rugosus, looks very similar to the Ecuadorian crabs except for a few key differences.The rugosus, or ruggie, comes in a variety of colors: black, blue, tan, gray, peach, and even white. Saltwater crabs are a large group of invertebrates within the decapod crustaceans family, consisting of several sub groups.