Synonyms: Notopterus chitala
Physical description: This elongated fish is high-backed with a long fin formed by the connection of the anal and caudal fins. The body color is silver-gray with four to ten distinct, black ocelli on the rear part of the body. Each ocelli is surrounded by a white area. The fins are somewhat darker gray.
Size/Length: To 40" (101 cm) in nature; not usually more than 18" in captivity.
Similar species: Resembles the African Knifefish ( Xenomystus nigri ) and the Asian Knifefish ( Notopterus notopterus ) when young.
Habitat: Southeast Asia; calm, overgrown backwaters of large rivers in Burma, India, Thailand
S: bottom, middle
Aquarium: 40" (100 cm) or 45-55 gallons (170-210 L) is sufficient for young individuals. When fish reach 12" (30 cm) they should be moved to an 60" (152 cm) or 90-110 gallon (340-410 L) tank. The tank should be dimly lit with a cover of floating plants. Provide hiding places with pipes, caves, wood, and rocks. Have densely planted areas, but leave large, open swimming areas.
Water chemistry: pH 5.5-7 (6.3), 2-10 dH (5), 75-82°F (24-28°C)
Social behavior: Small fish will be eaten, so combine with other large fish. The Clown Knifefish likes to form small, loose schools when young. Adults become more aggressive and territorial and should be kept singly.
Suggested companions: Arowana, Bichir, Oscar, Cichlasomines, Pimelodids, Loricarids, Asian Catfish, Giant Gourami
FOOD: Live; fish, Tubifex , snails, crustaceans, earthworms; occasionally pellets and tablets.
Sexual differences: Unknown
Breeding techniques: The pair will spawn in tanks with very soft water. The eggs are laid in floating plants and sometimes on hard surfaces. The male guards them, chasing off other fish and fanning the eggs. The eggs hatch after 6-7 days. Transfer the fry into a rearing tank. Start feeding with Artemia .
Breeding potential: 8. The main problem encountered in trying to breed this fish is the large size that must be attained to reach sexual maturity.
Remarks: Nocturnal. This fish is most active at dusk and daybreak. This fish is consumed by people in its native lands. A variation, the "Royal Knife" is also available. This type has more ocelli markings.
Difficulty of care: 6. A fish peaceful towards different species whose diet should include live foods.
Carbon dioxide (CO2) emissions generated from mongabay.com operations (server, data transfer, travel) are mitigated through an association with Anthrotect, an organization working with Afro-indigenous and Embera communities to protect forests in Colombia's Darien region. Anthrotect is protecting the habitat of mongabay's mascot: the scale-crested pygmy tyrant.
"Rainforest" is used interchangeably with "rain forest" on this site. "Jungle" is generally not used.