Aquarium species profile

Black Ghost Knifefish

Apteronotus albifrons · South America (Amazon basin — Venezuela, Peru, Bolivia, Brazil)

Minimum tank100 gal

Adult size20"

Care levelDifficult

TemperamentSemi-Aggressive

Temperature75–82°F

pH range6.0–7.5

Diet

Carnivore – bloodworms, tubifex, frozen shrimp, earthworms; can train to eat pellets

Compatible tank mates

Large peaceful fish (Oscars, large Plecos, large Severum), catfish

Tank mates to avoid

Small fish (will eat at night), conspecifics (highly territorial), other knifefish

Care notes

Uses a weak electrical field to navigate and hunt in the dark — electrosensory. Nocturnal. Extremely shy when young — needs PVC tube or hollow log to hide in. Grows very large slowly. One per tank; will fight its own kind. Fascinating and intelligent fish.

Check the whole aquarium. Tank size alone does not establish compatibility. Confirm adult size, water overlap, social grouping, territory, diet, and the individual animals before stocking.

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