Lawnmower Blenny

The Lawnmower Blenny is one of the most popular algae-eating fish in the marine aquarium hobby, earning its common name from its voracious appetite for filamentous and hair algae. This species features a mottled brown to greenish-brown body covered in tiny white to blue spots, giving it a jeweled appearance. Its comical facial expression, with large eyes set high on a blunt head, and its habit of perching on rocks while surveying its domain, give it an endearing personality.

As a dedicated herbivore, the Lawnmower Blenny spends nearly all of its waking hours grazing on microalgae and filamentous algae growing on rock surfaces, glass, and equipment. It is one of the most effective natural algae controls available for reef aquariums and can make a noticeable difference in algae growth within days of introduction. Its constant grazing keeps rocks clean and helps maintain the aesthetic appearance of the aquarium.

The Lawnmower Blenny is hardy and peaceful, making it suitable for beginner aquarists. However, care must be taken to ensure adequate algae growth in the tank or supplemental feeding with algae-based foods, as this species can starve in overly clean aquariums without sufficient grazing material. It is best kept singly, as conspecifics and similar blenny species will be treated as rivals in all but the largest aquariums.