The Clown Knife, also known as Clown Featherback, Spotted Knifefish, Spotted Featherback, is a very popular knifefish. This is partly because of its common availability and being relatively inexpensive. But its also a favorite because it is extremely attractive. They usually have a pattern of large spots, but this can be quite variable and it seems that no two Clown Knifefish are exactly alike.
The normal coloring of the Clown Knifefish is a silvery gray characterized by a variable pattern of large spots above the base of the anal fin. Yet sometimes they may have no spots at all, and sometimes they may have two rows of smaller spots. Other common names it is known by are Clown Featherback Fish, Spotted Knifefish, Spotted Featherback Fish, and Clown Knife. There is also an albino color form as seen in the picture above that’s called the Albino Clown Knifefish.
The Clown Knife has the typical knifefish body shape, flat and elongated with an arched back. Its anal fin and caudal fin (tail fin) are joined, giving it a long continuous fin along the underside. This fin undulates, allowing it to move either forwards or back wards, making it a very graceful swimmer.
Clown Knife Fish are suggested for an aquarist with some fish keeping experience. They can be hard to get adjusted to a new tank and this often results in death. This fish can grow to a substantial size, reaching about 3 1/2 feet (100 cm) in the wild. Specimens raised in the aquarium however, generally won’t grow much larger than 10 – 20 inches (25 to 50 cm). This is still a large fish, but since they are not particularly active they do not need as large of a tank as you might think. An adult can be comfortably housed in a 200 gallon (757 l) aquarium. Being nocturnal they need places to retreat during the day as well as open areas for swimming. Once acclimated, they are very hardy fish.
The C. ornata is It a member of the Notopteridae family which contains contains some of the more outgoing species of knifefish. They are generally peaceful and will do well with other fish that are not particularly aggressive and that are too large to fit into its mouth. Do take caution as they have poor eye sight and will some times try to eat bigger fish then they can handle. They can ultimately injury or kill a fish they are unable to eat.