African Knifefish

Xenomystus nigri

African Knifefish (Xenomystus nigri) — Varies care, Peaceful, under Other. Minimum tank in the app: 53 US gal min; aim for 73–82°F and pH 6.5–7.5. The African Knifefish is a captivating addition for aquarists seeking a solitary yet intriguing species, appealing for its unique swimming style and nocturnal activity.

African Knifefish (Xenomystus nigri) in a planted freshwater aquarium
Care levelVaries
TemperamentPeaceful
Min tank size53 US gal min
pH range6.5–7.5
Temperature73–82°F
Max size11.8 in (30.0 cm)
Captive lifespan6–10 years
SchoolingNo

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Africa

  • Africa

Regional colours match the stocking calculator’s origin map.

African Knifefish Tank Setup

Create a spacious environment with plenty of hiding spots using driftwood and plants to provide security and mimic its natural habitat. A soft substrate is ideal to prevent injury, and moderate water flow will facilitate its natural swimming patterns without overwhelming it. Maintain subdued lighting to encourage activity during dusk and dawn.

What Do African Knifefishs Eat?

This fish is an omnivore with a moderate feeding speed, often requiring a varied diet to thrive. Competition can arise if housed with faster, more assertive feeders, so offer food at varied times or locations to ensure equitable access and to promote vibrancy in coloration and overall health.

African Knifefish Tank Mates

The African Knifefish generally thrives alongside similarly-sized, non-aggressive species that occupy different swimming zones, such as larger tetras or peaceful cichlids. Avoid keeping it with overly boisterous fish that might stress it, and remember it prefers solitude, making intraspecies interactions minimal.

Are African Knifefishs Good for Beginners?

Care demand varies with setup and individual fish; use the numbers above as your baseline. Aquarists often underestimate the tank size and filtration needs for the African Knifefish, leading to poor water conditions and stress. failing to provide adequate cover can result in a timid fish that displays reduced activity and health issues over time.

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