Twinspot Goby

Also called the Signal or Crabeye Goby — a pale, dark-blotched sand goby whose two raised dorsal fins each carry a large eyespot, so that a fish seen from behind reads as the face of a much larger animal. It feeds by taking mouthfuls of sand and sorting out the interstitial worms, copepods and amphipods living in it, and this is the problem: almost no home aquarium has enough sand fauna to keep one alive, and a large proportion of imported specimens slowly starve even when they look healthy for the first few months. It needs a mature, deep, fine sand bed, a productive refugium feeding the display, no fast or boisterous tankmates competing for food, and daily target feeding of live and frozen foods — and even then results are mixed. Keep it as a bonded pair where possible, since separated fish tend to do poorly, and treat it as an advanced, deliberate purchase rather than an impulse one.