Red Pebble Crab

Geographical Origin and Habitat: Widely distributed in the tropical Indo-Pacific, particularly around the reefs of the Philippines, Indonesia, Micronesia, and Hawaii. Settles on shallow rocky reef substrates.

Taxonomy: Member of the family Xanthidae. Features a smooth, convex carapace measuring about 2-3 cm in width. Characterized by a fine, dense coat of short hairs (pubescence) on the legs and body. Grows to 2.5 cm.

Social Behavior: Peaceful, shy, and mostly active during the night. During the day it remains hidden inside deep rock crevices or dead coral skeletons. Harmless to tankmates.

Coloration and Sexual Dimorphism: Carapace color is solid bright red, deep pink, or reddish-orange. The short pubescence gives it a velvety, matte appearance. Claw tips are dark brown. No visible sexual dimorphism.

Tank Setup: Suitable for aquariums of 10 gallons or larger. Provide plenty of live rock with deep crevices and caves for day shelter. Does not require empty shells.

Diet and Feeding: Omnivorous scavenger and detritivore. Consumes microalgae, organic detritus, small worms, and leftover fish food. Accepts sinking pellets and chopped frozen foods.

Water Quality: Stable marine parameters: SG 1.020-1.025, pH 8.1-8.4, temperature 22-28°C. Highly sensitive to copper treatments and elevated nitrates.

Compatibility and Tankmates: 100% reef-safe. Great clean-up crew member. Compatible with peaceful reef fish and corals. Avoid keeping with large predatory fish.

Aquarium Breeding: Microscopic larval stages are pelagic and complex, and do not survive standard home aquarium filtration systems.

Risks and Diseases: Molting failure due to calcium, magnesium, or iodine deficiencies. Highly sensitive to copper treatments and sudden osmotic shocks.