Physical description: This elongated, laterally compressed fish has an arched back The body coloring is brown-violet to brown and the fins are lighter. The mouth is large, while the dorsal fin is small.
Size/Length: To 12" (30 cm)
Similar species: Asian Knifefish ( Notopterus notopterus )
Habitat: Northern Africa; still and slow-moving water of the Nile basin in Zaire, Gabon, Niger, and Liberia.
S: bottom, middle
Aquarium: A tank measuring 40" (101 cm) or 45-55 gallons (170-210 L) is sufficient. Follow suggestions under C. ornata .
Water chemistry: pH 5.7-7.5 (6.8), 2-10 dH (6), 73-82°F (23-28°C)
Social behavior: When young, this species does best when kept in a small group. Older fish become aggressive and intolerant of other Knifefish. This species can be combined with other medium to large sized species. Be aware that X. nigri will eat small fish.
Suggested companions: Haplochromines, Mormyrids, African Butterfly fish, African Tetras, Synodontis, West African Cichlids.
FOOD: Live; fish, earthworms, Tubifex , snails, insects, insect larvae, crustaceans; chopped meat; tablets, needs a varied diet.
Sexual differences: The female has a more rounded body around spawning times.
Breeding techniques: 150-200 eggs are laid at night in holes and crevices. The male guards the eggs, which hatch in 6-9 days. Transfer the fry into a rearing tank and start feeding with Artemia .
Breeding potential: 9. Breeding is difficult and infrequent.
Remarks: Nocturnal. The African Knifefish emits chiming bell-like sounds when swallowing air at the water surface. This species has a swim-bladder which serves as a respiratory organ. This fish rests in an oblique position with its head down. The African Knifefish emits barking sounds during courtship. This long-lived fish adapts well to tanks, but is shy when first introduced.
Difficulty of care: 5. This species requires a diet that includes live foods.