Blue-Leg Hermit Crab

Care at a glance

Overview

An active, mostly peaceful scavenger that is safe with corals and fish, so it counts as reef-safe. The catch is that it is not snail-safe: when it outgrows its shell it will kill snails, cerith snails especially, to steal theirs, and crowded hermits will fight each other over shells. Keep populations modest and always supply plenty of spare empty shells.

In the wild

This dwarf hermit comes from Caribbean reef and rubble zones and lives on and around the rock and sand, tucked into a borrowed snail shell. It wants an established reef with a good supply of algae and detritus to scavenge, plus a range of empty shells in different sizes so it has somewhere to move as it grows.

Good to know

Clibanarius tricolor is a small hermit, maxing out around 2.5 cm, with blue legs banded in orange-red and two equal-sized claws (hence the equal-handed nickname). It grazes green hair algae and cyanobacteria and cleans up leftover meaty food, making it a workhorse of the clean-up crew.

Did you know

Reef-safe does not mean snail-safe here: a blue-leg hermit will pull a cerith snail out of its shell and kill it just to upgrade its own home, so keep a stash of empty shells available.

Related species

• Mexican Red-Leg Hermit Crab

  Clibanarius digueti

  1 in (2.5 cm)11 gal (40 L)72–81°F (22–27°C)

• 

  Scarlet Zebra Hermit Crab

  Calcinus laevimanus

  1.2 in (3 cm)20 gal (75 L)72–79°F (22–26°C)

• 

  Scarlet Reef Hermit Crab

  Paguristes cadenati

  1.6 in (4 cm)11 gal (40 L)72–79°F (22–26°C)

• 

  Electric Blue Hermit Crab

  Calcinus elegans

  2 in (5 cm)20 gal (75 L)72–79°F (22–26°C)

• 

  Halloween Hermit Crab

  Ciliopagurus strigatus

  2 in (5 cm)20 gal (75 L)72–79°F (22–26°C)

• 

  Coral Guard Crab

  Trapezia cymodoce

  0.8 in (2 cm)11 gal (40 L)75–81°F (24–27°C)