Banded Knifefish (Gymnotus carapo) Care Guide
Gymnotus carapo is the most widespread South American weakly electric knifefish, a nocturnal, territorial predator with vertical banding.
Overview
Gymnotus carapo is a weakly electric knifefish of the family Gymnotidae and the most widespread species of the genus Gymnotus. The body is elongated and laterally compressed, marked with vertical brown bands. Like other gymnotiforms it generates a weak electrical field used for navigation, prey detection and communication, and it cannot produce the strong discharges seen in the electric eel.
Taxonomy
- Family: Gymnotidae
- Genus: Gymnotus
- Scientific name: Gymnotus carapo
- Describer: Linnaeus, 1758
Habitat
The species is widely distributed across South America, including the Amazon, Orinoco and Rio de la Plata basins, the Guianas, northeastern Brazil, northern Argentina and Trinidad. It occupies rivers, streams, floodplains, swamps and lakes, tolerates low-oxygen and polluted water, and can persist temporarily out of water if its habitat dries out.
Tank requirements
- Minimum tank volume: 400 L (106 gal)
- Temperature: 24-28 °C (75-82 °F)
- pH: 6.0-7.5
- GH: 4-15 °dGH
- Adult size: 30-60 cm (12-24 in)
- Lifespan: 8-12 years
- Provide low water flow and ample hiding places
Diet
Gymnotus carapo is a nocturnal carnivore. In the wild it feeds on benthic prey such as worms, insects and their larvae, crustaceans, small fish (preferably small characids) and some plant material. Its FishBase trophic level is about 3.6.
Compatibility
The species is nocturnal and highly territorial, reacting aggressively toward conspecifics. It is best housed individually with larger, non-fin-nipping tankmates such as larger tetras and catfish, while small fish should be avoided as they may be eaten.
Breeding
Males provide parental care, constructing and guarding a nest and brooding the young. Captive breeding is considered difficult.
Conservation status
IUCN Red List: Least Concern (assessed 9 July 2018). The species is of commercial interest in the aquarium trade.