Species group: Knifefish
Other common names: Featherback; Spotted Knifefish; Thousand Dollar Knifefish; Featherback Fish
Scientific name: Chitala ornata
The Clown Knifefish is a nocturnal, bottom-dwelling fish found in rivers and lakes throughout much of East Asia. Clown Knifefish can be very challenging to keep. Clown Knifefish are very undemanding fish provided their potential to grow is kept in mind. Once they adapt to their surroundings, they become hardy and live long. They are secretive by nature and will hide away from light. Clown Knifefish spend most of their time in the middle or at the bottom of the tank. They occasionally go to the surface to grab a gulp of air as these fish can also breathe air to survive in stagnant waters and in conditions of limited oxygen. They are nocturnal fish and they do not come out until twilight. They are predators and need to be feed live food like Guppies and Goldfish. Although they are tall, they are also narrow, which makes it possible for them to fit through very small spaces.
They can grow to more than two feet long in captivity (larger in the wild).The Clown Knifefish has a flat and elongated body with an elongated head, huge underslung jaw, and arched back. On the underside, they have a continuous fin formed by the union of the caudal and anal fin which covers two-thirds of the fish's body. This continuous fin makes it possible for them to swim rapidly both forwards and backwards. They have a small flag-like dorsal fin with six or seven fin rays located at the center of the body. They do not have ventral fins. The name ‘knifefish’ comes from the tail of the fish which resembles a sword blade. It is silver gray in color with a brown tinge and the fins are a darker gray.
The Clown Knifefish has a distinguishing characteristic: a variable pattern of large spots above the base of the anal fin. These distinct spots may range in number from four to ten. The series of large spots are black in color ringed with white. These circles increase in size and number as the fish grows and their pattern can vary immensely from fish to fish.
The juvenile Clown Knifefish has striped bands instead of spots. The center ridge along the belly is distinctly notched. These are nerve-filled pits that help the fish navigate in waters with low light. They have a large toothed mouth with a pair of short nasal barbels that help the fish while it is hunting. They have evolved to breathe atmospheric air in conditions when oxygen is less plentiful. It is perfectly normal for most Clown Knifefish to have a cloudy eye color as they age. They generally have poor eyesight. Apart from the silver-gray Clown Knifefish, an albino color form is also found.
Size: 24-40 inches
They are highly predatory to any fish they can fit into their large mouths, and are aggressive towards their own species.They tend to be timid and shy away from food and other fish when they are introduced into the tank.Knifefish can be housed together as schooling juveniles; as adults they become territorial, quarrelsome, and intolerant of other knifefish. Clown Knifefish are timid with larger tankmates, but they are also voracious predators capable of overpowering fishes of the same size and eating anything smaller. Adult Clown Knifefish that are 12" or larger should be housed with large fish such as Oscars, large Barbs, or peaceful large Cichlids. They can also be kept with Catfish, such as Synodontis and medium-sized Pims. They tend to be quite shy, skittish fish that panic easily when surprised. When hunting, they sneak up on small fish from behind and then pounce and swallow their prey whole.
Clown Knifefishes prefer still waters and can survive low oxygen levels. An external power filter with a spray bar which splashes at the water surface is preferable to creating a current around the aquarium to mimic the fish's natural habitat of slow-moving, placid water. Clown Knifefish are very greedy and consume large amounts of high protein foods which produce high levels of nitrate from the breakdown of wastes. Therefore about one fourth of the water must be changed on a weekly basis. Dim lighting is preferable. Sand can be used as substrate with some smooth boulders. These fish lack large scales or bony plates so sharp rocks and other jagged objects, which could cause injury must be avoided. A large swimming area is also required. For this reason, they should be kept in a very large aquarium of 100-300 gallons, that is well covered to deter jumping. They are nocturnal, so the tank needs to have numerous hiding places made from rocks, and driftwood. The aquarium can be densely-planted with bogwood and beech branches, and floating plants can be used to block out the daylight.
personalities, favorite freshwater fish, amazing predators, intermediate hobbyists
novice keeper, massive fish, HUGE tank, semiaggressive aquarium fish
nocturnal, long lifespan, good hiding places, shy clown knifefish