Bluehead Wrasse

Geographical Origin and Habitat: Tropical Western Atlantic, distributed from Florida and the Gulf of Mexico through the Caribbean to the northern coast of South America. Inhabits shallow coral reefs.

Taxonomy and Morphology: Labridae family, genus Thalassoma. Reaches 25 cm (10 inches). Elongated body. Exhibits three distinct life phases: juvenile, initial phase (female/primary male), and terminal phase (secondary male).

Social Behavior: Fast and active swimmer. Diurnal, buries itself completely in the sand to sleep or when frightened. Can be aggressive toward newly introduced tankmates.

Coloration and Sexual Dimorphism: Terminal phase males have an electric blue head, two black vertical bars separated by a white band, and a blue-green body. Females and initial phase males are bright yellow. Strong sexual dimorphism.

Aquarium Setup: Requires a tank of at least 300 liters with plenty of open swimming area. A fine sand bed of at least 5-8 cm (2-3 inches) deep is mandatory for burrowing. A secure lid is essential.

Diet and Feeding: Carnivorous. Feeds on small crustaceans and ectoparasites. Feed multiple times daily with frozen mysis, brine shrimp, krill, chopped shrimp, and quality pellets.

Water Quality: Temperature 22°C - 26°C, stable pH 8.1 - 8.4, salinity 1.020-1.025, KH 8-12, GH 15-25. Requires high filtration and good oxygenation.

Compatibility and Cohabitation: Semi-aggressive. May harass timid tankmates. Not safe with ornamental shrimp, crabs, or very small snails, which it will eat.

Aquarium Breeding: Protogynous hermaphrodite. Dominant females will change sex and transition into the colorful terminal male phase if the alpha male is removed. Captive breeding is rare.

Risks and Diseases: High jump risk; a tight-fitting lid or mesh net is mandatory. Coarse substrate can cause physical injury to the fish when it attempts to bury itself.