Clown Knife Fish

Geographic Origin and Biotope: Widespread throughout Southeast Asia (Mekong, Chao Phraya). Inhabits large slow-flowing rivers, lakes and swamps rich in vegetation.

Taxonomy and Morphology: Clown Knife Fish (Chitala ornata). Giant of the Notopteridae family. Easily reaches 1 meter (40 inches). Knife-blade compressed body, with a very long anal fin that it uses to swim in both directions.

Social Behavior: Nocturnal and crepuscular. Juveniles are gregarious, but adults become highly territorial and intolerant towards conspecifics or other similar fish. Swims sinuously on the bottom.

Coloration and Sexual Dimorphism: Silvery-gray background decorated with a row of large black "eyes" (ocelli) bordered with white along the base of the anal fin. The number of ocelli varies (from 5 to 10). Sexual dimorphism absent.

Aquarium Setup: Monster Tank species (minimum 200-250 cm / 80-100 inches in length). Needs huge PVC pipes or large submerged roots to hide during the day. Poor lighting and free swimming space.

Diet and Feeding: Voracious nocturnal predator. Wean it with dead small fish (smelt), shrimp, mussels and sinking pellets for carnivores. Will eat any fish that fits in its mouth.

Water Quality: Robust, tolerates a wide range of pH (6.0-8.0). Produces an enormous organic load: a giant sump and frequent heavy water changes are a must.

Compatibility and Tankmates: Coexists only with colossal sized fish that it cannot swallow: large Plecostomus, Pacu or large South American Cichlids. Conspecifics should be avoided.

Aquarium Reproduction: Impossible in domestic aquariums. In nature the male cleans a nest on the bottom or on submerged wood and fiercely defends the eggs (up to 10,000) and larvae for weeks.

Risks and Diseases: Very susceptible to Ich (White Spot) and sensitive to copper and malachite green based medicines due to its tiny scales. Use halved doses.