All fish / Apteronotidae

Brown Ghost Knifefish

Apteronotus leptorhynchus

Also known as brown ghost knife, brown ghost knifefish, longtail knifefish, brown knifefish, ghost knifefish, brown ghost, ブラウンゴースト, ブラウン・ゴースト・ナイフフィッシュ, 褐色魔鬼, 咖啡魔鬼刀

A long, slender, dark brown knifefish with no dorsal fin, a pale stripe along the back, and a few pale bands near the tail. It moves forwards and backwards with a rippling fin under its belly and senses its surroundings with a weak electric field, and people keep it for this unusual movement and behaviour.

Care at a glance

Care level

Moderate

Temperament

Semi

Adult size

25 cm

Temperature

23 to 28 °C

pH

6 to 7.5

Smallest tank

300 litres

Keep as

Singly, or several in a very large tank with many hiding places

Diet

Carnivore: bloodworm, blackworm, brine shrimp, mysis, small chopped seafood and sinking pellets, fed at dusk

Swims

Bottom of the tank

Lifespan

10 to 15 years

Water

Freshwater

Wild range

Northern South America: Orinoco and Amazon basins, Colombia, Venezuela, Guyana, Peru, Brazil

Breeding

It is rarely bred in home aquariums. Laboratory spawnings have been triggered by slowly lowering conductivity and imitating a rainy season, and the eggs are scattered among plants or rocks.

Good to know

It can grow larger than 30 cm and will eat small tankmates such as neon tetras. Adults can be territorial towards other knifefish, so give it a tube or cave to hide in and a tight lid.