Blue Starfish

Geographical Origin and Habitat: Tropical Indo-Pacific reefs. Found in shallow, sunlit reef flats and slopes, crawling over coral rubble and sandy patches.

Taxonomy: Family Ophidiasteridae, genus Linckia. Five thick, cylindrical arms radiating from a central disc, growing up to 30 cm in total diameter.

Social Behavior: Solitary, slow-moving, and peaceful. It does not interact with other tankmates and spends its time foraging on rock surfaces.

Coloration and Sexual Dimorphism: Famous for its solid, vibrant royal-blue coloration, though orange or purple morphs exist. No visual differences between sexes.

Tank Setup: Needs a mature reef tank of at least 300 liters. Plenty of high-quality live rock is essential to provide natural foraging surfaces.

Diet and Feeding: Omnivorous scavenger. Feeds on bacterial films, detritus, small sponges, and microalgae. Supplementation with algal sheets can be tried but success is low.

Water Quality: Demands pristine reef conditions. Maintain temperature at 22-26 °C, pH 8.1-8.4, and specific gravity 1.023-1.025. Nitrate levels must be kept low.

Compatibility and Tankmates: Entirely reef-safe. Avoid housing with predatory fish like puffers, triggers, or large crabs that may nip at its arms.

Aquarium Breeding: Extremely rare in aquariums. Can reproduce through fragmentation (autotomy) where a severed arm grows into a new starfish.

Risks and Diseases: Highly sensitive to copper treatments. Requires very slow drip acclimation (3-4 hours) to prevent fatal osmotic shock.