Description

• Scientific Name: Salarias fasciatus
• Common Names: Lawnmower Blenny, Jewelled Blenny, Algae Blenny, Sailfin Blenny
• Maximum Length: 5.5 inches (14 cm)
• Minimum Aquarium Size: 55 gallons (208 liters) for a single fish. Their perching and grazing habits need plenty of live rock and space.
• Foods and Feeding Habits: Herbivorous, primarily grazing on algae and detritus in the wild. In aquariums, offer nori seaweed, spirulina-based flakes or pellets, and algae-grown rocks. Supplement with frozen mysis or brine shrimp if needed. Feed 2-3 times daily, ensuring constant access to algae to prevent starvation.
• Reef Safety: Reef-safe; they excel at controlling algae without harming corals or most invertebrates.
• Temperament: Peaceful but territorial toward similar blennies or algae grazers. Best kept singly; compatible with non-aggressive tankmates like gobies or wrasses.
• Description: The Lawnmower Blenny is a useful algae eater with a quirky personality. Its mottled brown and green body provides excellent camouflage, paired with a sail-like dorsal fin and the ability to perch on rocks using pectoral fins. Native to the Indo-Pacific, from East Africa to Indonesia, they inhabit shallow reefs and lagoons with algae-covered rocks. Hardy once acclimated, they add entertaining behavior to the tank, often seen “mowing” surfaces clean.

Fun Facts:

• Lawnmower Blennies are facultative air-breathers, able to gulp air to survive in low-oxygen tide pools or weedy areas where water quality dips.
• They lay demersal eggs attached to substrates with a unique filamentous adhesive pad, and their larvae drift as plankton in shallow coastal waters before settling.
• In aquariums, they sometimes perform amusing “roaring” displays by flaring their fins at their own reflections, mistaking the glass for a rival intruder.