Black Ghost Knifefish care guide
Black Ghost Knifefish (Apteronotus albifrons) — minimum tank 400 L, temperature 23-28 °C, pH 6-7.5.
Compiled by Aquairi from published sources · Published · Updated
Overview
The Black Ghost Knifefish (Apteronotus albifrons) is an elongated, knife-shaped weakly electric fish from South America. It has a velvet-black body with two white bands across the tail and a long undulating anal fin used for both forward and reverse swimming. It is nocturnal and orients by a self-generated electric field.
Taxonomy
- Family: Apteronotidae
- Genus: Apteronotus
- Scientific name: Apteronotus albifrons
- Common synonyms: BGK
Habitat
Native to fast-flowing, sandy and rocky stretches of the Amazon basin and its tributaries in Venezuela, Peru and Paraguay. It shelters during the day under submerged logs, rocks and dense root mats in warm, slightly acidic to neutral water.
Tank requirements
- Minimum tank volume: 400 L (105.7 US gal)
- Adult size: 35-50 cm
- Temperature: 23-28 °C (73-82 °F)
- pH: 6-7.5
- GH: 2-15 °dGH
- Water flow: moderate
- Lifespan: 10-15 years
Diet
A nocturnal carnivore that takes worms, insect larvae and small crustaceans located by its electric sense. In aquaria it accepts frozen bloodworm, mysis, brine shrimp, chopped earthworm and sinking carnivore pellets once acclimated.
Compatibility
Peaceful but reclusive; conspecifics are territorial and only one specimen should be kept per tank unless very large (700+ L). Compatible with medium peaceful fish that share its requirements — Geophagus, Discus, Severum, large tetras and Corydoras. Small fish that fit in its mouth may be eaten at night.
Breeding
Captive breeding is rare and usually achieved only in large soft-water systems with rainy-season simulation. Females scatter eggs on plants or roots; reports suggest hormone induction is often required in aquaria.
Conservation status
IUCN Red List: Least Concern. The wild range across the Amazon basin is wide and the species is commonly captive-bred for the aquarium trade.
Black Ghost Knifefish Breeding Guide
Overview
Apteronotus albifrons is a weakly electric, nocturnal knifefish of the order Gymnotiformes. Like other gymnotiforms it is a fractional spawner, releasing its sticky eggs irregularly rather than in a single mass. Its fecundity is low, reported to range from 1 to 105 eggs.
Sexing
The species communicates and recognises gender through its electric organ discharge (EOD): females generate EODs at a higher frequency than males, a frequency-modulation difference that can be used for gender recognition. Reliable external visual sexing is not documented.
Spawning Behavior & Trigger
Spawning occurs at night, with eggs deposited between roughly 11 pm and 2 am. The fish use their electrosensory object-location ability to hide eggs one at a time in tiny holes or gaps. When more than one male is present a single male is chosen to spawn and rivalry occurs between males. The species is a fractional (irregular) spawner.
Egg & Fry Care
The eggs are sticky and are concealed individually in small crevices. Because total fecundity is low (1 to 105 eggs) and eggs are scattered into hiding places rather than laid in a tended nest, locating and rearing fry is difficult. No detailed fry-rearing protocol is documented in the sources consulted.