Lawnmower Blenny (Salarias fasciatus) aka the jeweled blenny, jeweled rockskipper, or sailfin blenny, can reach a size of 5.5 inches, and should be kept in a tank no less than 30 gallons. They are a brownish color with various spots making them excellent at camouflage.
They should be housed in a tank with plenty of live rock, and an abundance of algae growth. The lawnmower blenny are known to be very beneficial members in any saltwater aquarium and often purchased for it's ability to eradicating algae, as they will sit at the bottom scraping rocks and the walls of the aquarium with its specialized teeth as it searches for algal deposits.