Electric Blue Hermit Crab

Calcinus elegans, the Electric Blue Hermit Crab, is one of the most visually striking hermit crabs in the marine hobby. Its legs shimmer in vivid iridescent blue banded with bright orange-red, while black-tipped claws and fluorescent orange antennae complete the spectacular color display. Beyond its ornamental appeal, it is a dependable worker in the clean-up crew, grazing on film algae, cyanobacteria, detritus, and uneaten food from rocks and substrate. Its small size makes it suitable for nano reef aquariums as small as 40 liters. Provide a selection of empty shells in varying sizes to accommodate molting and growth.

Supply several empty shells of varying sizes so the crab can choose a new home after molting. Supplement feeding with algae wafers or dried seaweed if natural algae supply is limited. Reef-safe with corals and most invertebrates, though may harass very small snails for their shells. Maintain stable salinity of 1.024–1.026 SG and good water quality for long-term health.