Six-spot Goby

The Six-spot Goby, or Spot-headed Sand Sifter, is a hard-working fish with a pearly white body and several small, iridescent blue spots on its cheeks. Its primary behavior, and the reason it's so popular, is its constant sifting of the sand bed. It takes large mouthfuls of sand, filters out edible organisms, and expels the clean sand through its gills, keeping the substrate clean and aerated. It must be kept in an aquarium with a mature, deep sand bed to survive. An interesting fact is that these gobies form monogamous pairs, often sharing a burrow which they diligently maintain together.