Bit long winded this article but might help .
Many of the blennies are algivores, and because of this, they are often introduced to the aquarium to control hair algae. The most popular with aquarists are the lawnmower blennies (especially the jeweled or lawnmower blenny [Salarias fasciatus]). The 13 species in the genus Salarias belong to the subfamily Salariinaeand are often collectively referred to as combtooth blennies. They are not the most colorful members of the family, but the color usually consists of bands, stripes, and spots in hues of brown, green, and cream. Their color patterns typically help them to disappear against the reef substrate.
The Salarias species are residents of tropical, shallow coastal habitats. They typically are found on fringing reefs or on lagoon patch reefs and rubble patches. These blennies regularly live among coral rubble, macroalgae, or branching stony corals or at the base of sponges. Salarias spp. are most often found at depths of less than 15 meters (50 feet). There is one newly described species (in 2005), S. reticulatus, that inhabits fresh water in south India.
These blennies pound the substrate with their flexible jaws and comb-like teeth. While they do eat some algae (the amount varies from one species to the next), recent studies have shown their primary source of food is detritus in the form of detrital aggregates. Because detritus is often overlooked in food-habit studies, its importance as Salarias food has long been overlooked.
These blennies scrape this material off hard surfaces (e.g., coral rock, dead coral skeletons), along with some algae. They will also incidentally ingest tiny invertebrates. For example, the diet of S. fasciatus has been reported to include filamentous algae, diatoms, foraminiferans (shelled protozoa), tiny crustaceans, detritus, and sand.
On occasion, this species will also consume fish eggs, sponges, and small snails. They ingest a significant amount of calcium carbonate as they feed, which is not uncommon for herbivores with less selective feeding tactics. While many of the Salarias spp. eat some algae, some steer away from the filamentous forms that can overgrow our aquariums. For example, S. patzneri selectively feeds on smaller particles less than 125 mm in size (mainly detritus) and avoids those in excess of 250 mm (that is, algal filaments).
These blennies lay demersal eggs, which they deposit in shells (e.g., empty tridacnid valves). The male tends the eggs until they hatch.
Hope this helps