Blue Leg Hermit Crab

Looks how to spot one

Hard front body with a soft abdomen kept inside a borrowed snail shell

A tiny hermit crab with bright blue legs banded in red at each joint and two claws of equal size. It lives in empty snail shells and trades up as it grows.13

Personality what they are like

Peaceful and sociable. It rests by day and gets busy around dusk, feeding through the night. Hermits squabble over shells, flipping and spinning a rival to win its home.13

Daily activity how busy a day looks

Active at night, moving around in groups to forage over rocks and sand and sifting the substrate as it goes.1

Grooming and care the hands-on bits

Rated easy. Keep plenty of spare empty shells and enough food on offer, as hungry or house-hunting crabs may compete with snails for shells. Add dried seaweed if algae runs low.3

Home where they are happiest

A marine reef aquarium with live rock and sand. LiveAquaria gives 72-78 °F (about 22-26 °C), pH 8.1-8.4, dKH 8-12 and specific gravity 1.020-1.025. Wild crabs live on rocky bottoms in very shallow water. No minimum tank size was given by the sources.31

Food basics what goes in the bowl

An omnivore and detritus eater that picks at dead organic matter, hair algae, cyanobacteria and seaweed, and sifts sand for food.13

Company who they like around

Lives in groups in the wild; several can be kept together in larger tanks. Peaceful with fish and corals.13

The story where it all began

Gibbes described the species in 1850. Its bright colours and its habit of eating algae and detritus have made it a popular clean-up crew animal for home reef tanks.1

Recognised by the official bits

Taxonomy (via Wikipedia)

Described by Gibbes in 1850; family Diogenidae.1

IUCN (via SeaLifeBase)

Not Evaluated.2