Salarius fasciatus. Also known as the Lawnmower Blenny.
The lawnmower blenny is a fish full of character and has become popular for its effectiveness in algae control. It is a very active fish grazing all day on both the rocks and the glass panes of aquariums and leaves its trademark lipstick marks on the glass panels as it comically bangs its head on the glass surface to graze on diatoms and other algae. A well established specimen is very tame and eager to take feedings from your hand. This blenny is classified as a combtooth blenny meaning that it has raspy teeth that are effective in removing algae. Primarily it will graze on diatoms, other film algae and some hair algae. It is not known to feed on hair algae that is overgrown and is also not likely to be effective in keeping slime algae under control.