Scarlet Hermit Crab (Paguristes cadenati)

The Scarlet Hermit Crab, scientifically named Paguristes cadenati, is valued in aquariums for its ability to eat hair algae and scavenge. These crabs typically grow to fit into shells about 1.5 inches long.

While they’re usually safe to keep with corals, they can be a threat to snails and other hermit crabs, as they often seek new shells. Providing plenty of empty shells can help reduce this aggressive behavior. As they grow, they tend to prefer medium to large shells. Native to Florida, Scarlet Hermit Crabs are effective at cleaning tanks, but their collection from deep waters can make them a pricier option.