Aquarium Livestock Pet Care Guides



Indo-Pacific, Africa

Average Size

Varies by species


3 -10 years


Knifefish are primarily carnivores (meat/fish eaters). Provide a varied diet of frozen or live blackworms, bloodworms, glassworms, wigglers, beefheart, small fish (especially for larger clown knives but only as a treat), and herbivorous food such as plankton or wafers. A diet based solely on feeders will result in vitamin deficiencies and sick fish.


Peaceful to other fish not small enough to eat. Larger clown knives will be aggressive to their own kind and even to larger tankmates, especially in cramped quarters.

Tank Environment

Knifefish are shy and primarily nocturnal fish. Dim aquariums with lots of cover (plants, driftwood, PVC tubes), just enough for moderate water movement. Remove uneaten food to prevent water fouling. Maintain good water quality. Provide sandy bottom or other soft substrate and smooth decorations, knives can scratch easily as they cruise around.

Common Species

Black African Knifefish-Xenomystus nigri
Max. Size: 8"
Country of origin: West Africa
Temperament: Very shy and peaceful. Prefers calm, vegetated tanks.

Clown Knifefish-Chitala chitala (similar C. ornata)
Max. Size: 48"
Country of origin: India to S.E Asia
Temperament: Tolerant of own kind only when small, best kept as single specimen in tank when adults. Will eat anything small enough to fit in its mouth.
Additional Information: Also available in Albino coloration, though very rare and expensive. Adults develop deep sloping "humped" shape.

Royal Clown Knifefish-Chitala blanci
Max. Size: 48"
Country of origin: Laos
Temperament: Same intolerance of others as Clown Knife
Additional Information: Beautiful silver with tire tread patterning, usually more expensive than standard clown knives.