Yellowtail Coris

Geographic Origin and Biotope: Tropical Indo-Pacific, from East Africa and the Seychelles to Hawaii, the Tuamotu Islands, and southern Japan. Inhabits sand-reef zones.

Taxonomy and Morphology: Labridae family, genus Coris. Reaches 40 cm (16 inches). Elongated body. Juveniles have a bright orange livery with black-edged white saddles, completely different from adults.

Social Behavior: Large, active diurnal swimmer. Buries itself in the sand to sleep or escape danger. Known to flip small rocks and rubble to search for prey.

Coloration and Sexual Dimorphism: Adults are dark greenish-brown with numerous bright blue spots on the body, a red head with green stripes, and a bright golden-yellow tail. Juveniles are orange and white.

Aquarium Setup: Requires a very spacious tank of at least 600 liters. A fine sand bed at least 8-10 cm (3-4 inches) deep is mandatory for burying. A secure, tight-fitting lid is essential.

Diet and Feeding: Carnivorous. Feeds on hard-shelled invertebrates. Feed chopped whole shrimp, mussels, clams, krill, and premium dry pellets.

Water Quality: Temperature 22°C - 27°C, stable pH 8.0 - 8.5, salinity 1.020-1.025, KH 8-12, GH 15-25. Clean water with high oxygenation is required.

Compatibility and Tankmates: Semi-aggressive. Not reef-safe; will consume ornamental shrimp, crabs, hermit crabs, and small snails. Ignores corals but may knock them over while searching for food.

Aquarium Reproduction: Protogynous hermaphrodite. Dominant terminal males transition from mature females. Not commonly bred in home aquariums.

Risks and Diseases: Extreme jump risk. When startled, it dives headfirst into the substrate; avoid placing rocks directly underneath the sand to prevent head injuries.