Electric Blue Hermit Crab (Calcinus elegans)

The Electric Blue Hermit Crab (Calcinus elegans) is a beloved reef aquarium invertebrate renowned for its extraordinary coloration — electric blue legs boldly banded in bright orange give it a truly exotic appearance unlike any other hermit crab in the hobby. It is a diligent grazer that methodically works through hair algae, cyanobacteria, and organic waste on rock surfaces and sandy substrates, making it a valuable member of any reef clean-up crew. Its compact size suits nano reef setups and larger reef systems alike. Always provide a selection of progressively larger empty shells to allow healthy molting and growth.

Provide an assortment of empty shells in several sizes for molting. Supplement diet with algae wafers if live algae supply is limited. Generally peaceful and reef-safe; may occasionally evict smaller snails from shells. Maintain stable saltwater parameters — salinity 1.024–1.026 SG, alkalinity 8–11 dKH. Avoid copper-based medications, which are lethal to all invertebrates.