Black ghost knifefish

The black ghost knifefish reaches about 50 cm total length in the wild and is one of the most distinctive freshwater fish in the hobby — an elongate, ribbon-like body in deep velvety black with two white bands on the tail and a white blaze on the snout. It comes from the Amazon and Orinoco basins across much of northern South America. A full-grown adult needs a tank well over 300 L with a large swimming area and no sharp decorations that could injure its scale-less body. Temperature of 23–28 °C and pH 6.0–8.0 suit it. It navigates and hunts using a weak electrical field; the body contains electroreceptors that sense disturbances in the field. Diet is carnivorous — bloodworm, chopped prawn, earthworms, and frozen foods; it eventually accepts sinking pellets. It is peaceful toward fish too large to swallow but will eat small tankmates. Despite a reputation for skittishness, it becomes recognisable to its keeper and will feed from the hand over time. The species is a weak swimmer and needs gentle filtration — strong current stresses it.