Limit: no more than 1 per tank. Belligerent to conspecifics; one per tank (ACO advises against two).
Predator: may eat fish up to about 8 cm.
Check a tank with Black ghost knifefish
Good tank mates for Black ghost knifefish
These species share its temperature range and temperament, with no fin-nipping or predation risk under our rules. Still check your tank size and bioload in the checker.
African butterflyfish · Angelfish · Banded archerfish · Blue acara · Chinese algae eater · Clown loach · Common pleco · Convict cichlid · Dwarf gourami · Electric yellow lab · Firemouth cichlid · Flying fox · Giant danio · Jack Dempsey · Jewel cichlid · Kissing gourami · Kribensis · Oscar · Peacock cichlid · Pictus catfish · Rainbow shark · Red-tail shark · Sailfin molly · Sailfin pleco
Avoid with Black ghost knifefish
African dwarf frog (predation) · Agassiz's dwarf cichlid (predation) · Amano shrimp (predation) · Assassin snail (predation) · Betta (male) (predation) · Black neon tetra (predation) · Black phantom tetra (predation) · Black ruby barb (predation) · Black skirt tetra (predation) · Bleeding heart tetra (predation) · Bloodfin tetra (predation) · Bolivian ram (predation) · Bronze corydoras (predation) · Buenos Aires tetra (predation) · Bumblebee goby (predation) · Cardinal tetra (predation) · Celestial pearl danio (predation) · Checkerboard barb (predation)
Sources
Checked 2026-11-09 · confidence: high. These are cautious community guidelines, not guarantees. Not veterinary advice. Report an error.