Black Ghost Knifefish

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Species group:

Other common names: BGK

Scientific name: Apteronotus albifrons

The basics:
The Black Ghost Knifefish is a nocturnal member of the Ghostfish family, and is native to fast moving streams in tropical river basin environments such as the Amazon basin in Peru. Black Ghosts find their prey by generating a weak electrical charge serving like a radar detector, also known as electro-sensing. They are nocturnal and can be better observed with a night light or moon lighting fixtures. Black Ghosts are carnivorous and will eat live or freeze-dried foods, flakes, and pellets.

True to its name, the Black Ghost Knifefish has an undulating laterally compressed knife-shaped body that is jet black in color. Two contrasting white markings appear on the head (a blaze originating from the nose rising above the head and often extending halfway down the back) and tail (a pair of wide vertical bands around the rounded tail). The long anal fin starts at the base of the pectoral fins. The dorsal fin is small and filamentous. The eyes usually blend in with the body color.

0-20 inches

They are shy but can also be aggressive towards their own kind; therefore, are best kept alone, with similar-sized, non-aggressive tank mates.

Black Ghost Knifefish require a 30-40 US gallon tank (95-110 liter) when small, but can grow as large as 12 inches. They prefer dim light as they use a weak electrical pulse to see, and like to hide in wood or a plastic tube. Black Ghosts are a large species ideally housed in at least a 50-gallon tank equipped with assorted plants and sufficient hiding places. Floating plants the dim the overhead lights are recommended because Black Ghosts are shy and tend to hide from bright light. The best hiding places are driftwood and opaque or transparent pipe tubes. The recommended substrate is fine grained and dark colored. Aquarium should be shaded with a dark substrate and a well planted interior for hiding places

73.00-82.00 °F


50.000-100.000 mg/L


interesting, hardy fish, senses electric signatures, unique shape, unusual fish


special feeding requirements, nocturnal species, hiding habits, steady temperature, shy fish


hiding places, tight small places, electrical sensory organ, voracious appetite

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