Black Ghost Knife Fish

Black Ghost Knife Fish (Apteronotus albifrons)

One of the most distinctive freshwater fish available, the Black Ghost Knife has a sleek, jet-black body with a white blaze on its nose and an undulating fin running along its underside. Nocturnal and fascinating to watch, it uses a weak electric field to navigate — a true centrepiece for a large, species-focused tank.

Care at a Glance:

• Minimum Tank Size: 300L+ with hiding spots, caves, and dim lighting
• Temperature: 24–28°C
• pH Range: 6.0–7.5
• Water Hardness: Soft to moderate
• Temperament: Peaceful but predatory; will eat small fish
• Diet: Frozen bloodworms, blackworms, brine shrimp, sinking pellets
• Max Size: 30–40cm (aquarium), up to 50cm
• Lifespan: 10–15+ years
• Care Level: Moderate (needs space, hiding spots, and pristine water)

Tank Mates: Large, peaceful community fish such as medium cichlids, large catfish, and rainbowfish; avoid small fish that could be eaten and aggressive species.

Origin: South America — Amazon Basin (Brazil, Peru)