African Knifefish

African Knifefish (Xenomystus Nigri)

African Knifefish, also known as Brown Knifefish, are unique, nocturnal freshwater fish that are native to the slow-moving waters of West and Central Africa. They have a distinct elongated, knife-shaped body with a dark brown to black coloration and a white stripe running from their head to the tail.

As for the care, the African Knifefish is considered an intermediate-level fish, as they require specific tank conditions and a well-thought-out diet. They grow up to 8-12 inches in size, although 8 inches is usually considered an average size for a captive breed species. They should be kept in a small school of 3-4 individuals.

African Knifefish has a peaceful temperament but can be territorial with their own kind. They are compatible with peaceful to semi-aggressive tank mates that are too large to be considered prey. African Knifefish generally coexists peacefully with other fish, provided they are too large to be consumed overnight. However, they exhibit territorial behavior toward their own kind and other knifefish species, so it is best to keep only one per tank and avoid mixing with other knifefish types. Suitable tankmates should have a similar temperament and be large enough not to be seen as prey; appropriate companions might include Angelfish, Eartheaters, medium-sized Gouramis, medium-sized Tetras, large Rainbowfish, African Butterfly Fish, and Synodontis Catfish. Refrain from housing African Knifefish with aggressive or overly active species, and do not keep them with snails or shrimp, as they are likely to be hunted.

The African Knifefish is a carnivore, and its diet consists of small fish, insects, and crustaceans. Live or frozen foods are preferable but may also accept high-quality sinking pellets. They tend to be more active during the night, so offering them food in the evening is recommended. 

The ideal tank habitat should replicate their natural environment, with plenty of hiding spots, such as caves, driftwood, and dense vegetation. A dimly lit tank with a sandy substrate is recommended. Gentle water flow and excellent filtration are essential for their well-being.

The African Knifefish is relatively easy to care for as long as certain essential conditions are met. First, since this fish grows quite large and has limited flexibility, it requires a spacious aquarium (at least 4 feet long and a minimum of 18 inches wide). Second, the knifefish should be given various shady hiding options, such as wide PVC pipes, horizontally placed flowerpots, stable rocky caves or overhangs, and large clusters of driftwood.

As these nocturnal fish are sensitive to intense light, the aquarium lighting should not be overly bright. If bright lighting is necessary for some parts of the tank, use broad-leaved aquatic plants and floating species to help diffuse the light. It is crucial to have dark areas in the tank where the fish can retreat during the day as needed.

Adequate filtration, moderate water flow, oxygenation levels, and a consistent maintenance routine that includes weekly water changes of 30-50% are essential for the African Knifefish, as it is sensitive to high nitrate levels and sudden shifts in water chemistry. Knifefish do not have scales, making them susceptible to injuries and infections. Therefore, installing a UV sterilizer in the tank may be wise to eliminate pathogens and safeguard against the need for using chemical treatment in their water.

The minimum aquarium size is 50 gallons, with an ideal community tank size of 75 gallons or more. Maintain a pH of 6.0-7.5, a hardness between 5-12 dGH, and a temperature range of 75-82°F (24-28°C).

African Knifefish, like many other fish species, have the potential to jump out of the aquarium if given the opportunity. To minimize this risk, it is essential to have a well-fitted and secure lid or cover on the tank. This will prevent the fish from jumping out and help maintain the tank's water quality by reducing evaporation and limiting the introduction of foreign contaminants.