A massive, nocturnal predator native to Southeast Asia, widely known for the distinct row of ocellated spots above its anal fin. While sold as small silvery cute juveniles, they grow incredibly fast into nearly 1-meter giants that require immense aquariums. They are obligate carnivores and will eat any fish small enough to fit in their large mouths. They are shy during the day and require large hiding tubes or caves.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard (Adult)
The fully grown adult form. Requires a tank with a footprint wide enough for it to turn around (at least 75cm width recommended). Highly territorial towards other Knifefish.
Differs in 1 trait from base species
Also known as: Adult, Monster Fish
Juvenile (Grow-out)
Commonly sold size (10-15cm). Deceptively peaceful and shy. WARNING: Grows extremely fast. Will eat neon tetras and guppies immediately. Requires an upgrade plan to a 200G+ tank within 12-18 months.
Differs in 5 traits from base species
Also known as: Baby, Small
Albino / Golden
A color morph lacking the dark grey pigmentation. Care requirements are identical to the standard form.
Differs in 1 trait from base species
Also known as: Platinum, Gold
Clown Knifefish Care Summary
The Clown Knifefish, scientifically known as Chitala ornata, belongs to the Oddballs family group. Adults reach a maximum size of approximately 90 cm and have a compressed body shape with a fast growth rate. Classified as aggressive, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a extreme level of biological waste.
To thrive, the Clown Knifefish requires a freshwater only aquarium with a minimum volume of 750 litres and a tank length of at least 180 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 6–7.5 and a general hardness of 5–15 dGH. A moderate water flow is preferred. To replicate their natural habitat, the tank should include smooth gravel (sensitive barbels), driftwood (digestion/hiding), and plants - densely covered.
Only one Clown Knifefish should be kept per aquarium. Keepers should be aware that this species will prey on fish small enough to fit in its mouth, can be aggressive toward its own kind, is a known jumper, so a tight-fitting lid is essential, and is primarily active at night or during twilight hours. This species is available in 3 varieties: Standard (Adult), Juvenile (Grow-out), and Albino / Golden. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Similar Species
Black Ghost Knifefish
Apteronotus albifrons
A fascinating nocturnal predator native to the Amazon basin. It lacks a dorsal fin and moves via a continuous undulating ventral fin, allowing it to swim backwards as easily as forwards. It generates a weak electrical field to navigate and hunt in the dark. Scaleless and highly sensitive to medications, it requires smooth hiding places (like PVC pipes or smooth driftwood). Will consume any fish small enough to fit in its surprisingly large mouth.
Florida Flagfish
Jordanella floridae
A robust, deep-bodied killifish native to Florida. Unlike most killifish, they are primarily herbivores and are renowned for their ability to eat Hair Algae and sometimes Black Beard Algae. They are sub-tropical and thrive in unheated aquariums. They can be fin-nippers, especially if underfed or kept with long-finned tank mates.
Red-Tail Catfish
Phractocephalus hemioliopterus
A massive, fast-growing predatory catfish from the Amazon basin. Famous for its voracious appetite, bulldozer-like behavior, and distinct red caudal fin. Due to its enormous adult size (often exceeding 4 feet), it is strictly a 'monster fish' that requires a heated indoor pond or a colossal custom aquarium. It is highly predatory and will swallow absolutely any tank mate that can fit into its cavernous mouth.
Clown Loach
Chromobotia macracanthus
A highly popular but large-growing shoaling fish famous for eating nuisance snails. Known for their striking orange and black bands, they are highly social and must be kept in groups. They have no standard scales, making them sensitive to medications and prone to Ich, requiring pristine, warm water. They are known for their quirky behavior of sleeping on their sides or backs.
Clown Killifish
Epiplatys annulatus
A striking nano killifish resembling a tiny rocket. Native to West African swamps, they have distinct black and yellow vertical bands. They are strictly surface dwellers (top-level) and are non-annual, meaning they live longer than annual killifish (2-3+ years). They are notorious jumpers and require a tight lid.
Panda Corydoras
Corydoras panda
A highly popular, peaceful schooling catfish easily identified by its black eye patches and spotted dorsal/tail fins, resembling a giant panda. Native to the cooler waters of the Ucayali river system in Peru, they require slightly lower temperatures than many standard tropical community fish. They are strict bottom-dwellers that sift through the substrate for food.