Useful for controlling microalgae on live rock and corals, these reef-safe herbivores pack plenty of personality, darting from perch to perch among the rockwork. Body coloration graduates from a primarily blackish-purple body to an electric indigo and yellow-white tail.In nature, they are most commonly found among the shallow reef flats, but also inhabit estuaries and outer reef lagoons to about 60 feet deep. Combtooth Blennies are named for their distinctive fine teeth - about 100! - embedded in their lips rather than their jaw. They use these teeth to scrape algae off rocks and aquarium glass.