Linear Blenny

Geographic Origin and Biotope: Tropical Indo-Pacific: from the Gulf of Aden and Mauritius to Micronesia, north to southern Japan, and south to the Great Barrier Reef. Inhabits protected lagoons and outer reefs rich in corals at depths of 1 to 20 meters.

Taxonomy and Morphology: Belongs to the family Blenniidae, genus Ecsenius. Features a scaleless, elongated cylindrical body, protruding mobile eyes, and small nasal cirri. Reaches a maximum length of 9 cm.

Social Behavior: Primarily solitary and territorial over its grazing rocks. Likes to perch on rocky ledges, observing its surroundings with curiosity.

Coloration and Sexual Dimorphism: Upper body is dark brown or black with distinct yellow or whitish horizontal lines running from the eyes to the tail. Adult males are slightly larger than females.

Aquarium Setup: Demands a tank of at least 100 liters with plenty of live rock providing small holes and caves. A tight-fitting lid is mandatory as this species is a skilled jumper.

Diet and Feeding: Specialized herbivore. In captivity, requires mature rockwork with natural algae growth. Supplement with spirulina-based foods, shredded nori, and sinking herbivore pellets.

Water Quality: Stable water parameters and good oxygenation. Temperature 23-27°C, pH 8.1-8.4, salinity SG 1.020-1.026. GH 15-25. Nitrate levels should be kept low to protect fish health.

Compatibility and Tankmates: 100% reef safe, does not bother corals. Avoid housing with other Ecsenius species or blennies of similar shape unless the tank is very large. Peaceful with other fish classes.

Aquarium Reproduction: Extremely difficult and undocumented in commercial hobbyist setups. Spawns adhesive eggs in crevices or empty shells, which are then guarded by the male.

Risks and Diseases: Starvation in newly set-up aquariums lacking microalgae is the main risk. Sensitive to copper treatments and bacterial skin infections if scraped on sharp rocks.