Red-claw Hermit Crab

Geographical Origin and Habitat: Widely distributed in the Mediterranean Sea, Black Sea, and Eastern Atlantic coasts from the English Channel to the Azores. Inhabits rocky intertidal zones and shallow tide pools.

Taxonomy: Classified under the Diogenidae family. Features short legs and equal-sized claws covered in small tubercles and sensory hairs.

Social Behavior: Peaceful, gregarious, and active scavenger. Spends its time crawling over live rock and substrate. May fight with conspecifics only if empty shells are scarce.

Coloration and Sexual Dimorphism: Body is greyish-brown or olive-green. Walking legs and claw tips exhibit a bright red or vivid orange coloration. Sexual dimorphism is not externally visible.

Tank Setup: Suitable for Mediterranean or temperate setups of 10 gallons or larger. Requires a steady supply of empty snail shells of various sizes and live rock for climbing.

Diet and Feeding: Omnivorous, mainly herbivorous and detritivorous. Consumes hair algae, diatoms, organic debris, and leftover fish food. Eats pellets, flakes, and frozen food.

Water Quality: Prefers cool temperatures between 15°C and 24°C (avoid keeping above 25°C long-term). pH 8.0-8.4, salinity SG 1.024-1.027. Strictly zero copper levels.

Compatibility and Tankmates: Reef safe and harmless to fish. May attack snails if it needs a larger shell for growth. Best kept with calm, temperate fish.

Aquarium Breeding: Females carry eggs under their abdomen. The larvae are released as pelagic zoea, which do not survive in standard home filtration systems.

Risks and Diseases: Fights with snails over shells if replacements are missing. Highly sensitive to copper treatments and sudden specific gravity changes.