Collector Urchin

Geographical Origin and Habitat: Widely distributed throughout the tropical Indo-Pacific, from East Africa and the Red Sea to Hawaii. Inhabits shallow coral reefs, lagoons, and seagrass beds.

Taxonomy: Member of the Toxopneustidae family. Features a globose shell covered with short spines interspersed with sections of tube feet and pedicellariae. Diameter reaches 10-15 cm.

Social Behavior: Solitary and peaceful toward other inhabitants. An active and efficient grazer that constantly scrapes algae off rocks and aquarium glass.

Coloration and Sexual Dimorphism: Spinage color varies greatly, including white, black, purple, orange, and brown bands. No visible external sexual dimorphism.

Tank Setup: Requires an established marine tank of at least 150 liters with plenty of live rock.

Ensure all rocks and corals are glued down:, as the urchin can easily bulldoze unsecured items.

Diet and Feeding: Voracious herbivore. Feeds primarily on nuisance microalgae, film algae, and macroalgae (including Caulerpa). Supplement with dried seaweed (nori) if natural food is depleted.

Water Quality: Requires stable marine parameters: specific gravity 1.023-1.025, temperature 22°C-26°C, pH 8.1-8.4. Highly sensitive to elevated nitrates.

Compatibility and Tankmates: Reef-safe. Do not keep with predatory fish that feed on urchins, such as puffers, triggerfish, or large wrasses.

Aquarium Breeding: Broadcast spawner, releasing gametes into the water column. Captive breeding in standard aquariums is unsuccessful due to the delicate pelagic larval stage.

Risks and Diseases: Intolerant to copper treatments and rapid salinity drops. Spontaneous shedding of spines is a major warning sign of stress or poor water chemistry.