Fish, Tanks and Ponds


Fish, Tanks and Ponds
A comprehensive guide to fish

Rasbora kalochroma

Clown Rasbora

Clown Rasbora, Rasbora kalochromaClown Rasbora, Rasbora kalochroma
Photos by Andy Rapson

Etymology:

Rasbora: Rasbora, an Indian word for a fish, also used in Malay peninsula

General Notes:

Clown rasboras live in forest streams which are heavily stained with tannins. As a result direct sunlight doesn't penetrate in to their environment and so the species does best in a low light set up. Bogwood, rockwork, twigs and dried leaves make ideal naturalistic decor for their aquarium. Clown rasboras are quite large and they are extremely active swimmers, as such they require a relatively large aquarium for their size. 250litres (typically a 48" x 18" x 18" aquarium should be considered the minimum size for a group of these fish. It is essential that these fish are kept in soft acidic water if they are to thrive. Groups of clown rasboras should have a ratio of one male to two females if possible and ideally at least twelve individuals.

Feeding

In the wild their diet consists of mostly small inverts such as worms, crustaceans and molluscs. In captivity they are relatively unfussy and will accept a range of prepared food such as flake, suitably sized pellets but these should not be used alone. Fresh meaty food such as live or frozen bloodworms, daphnia, cyclops, brine shrimps, glass worms all should be a part of their regular diet in order to keep the fish in top condition.

Compatibility

Clown Rasboras are reliably peaceful and make excellent community fishes with other peaceful fish of a similar size.

Sexing

Females are slightly larger and more heavily built, males exhibit the more vibrant colours.

Breeding

With good care fry may appear on a regular basis in the aquarium but the fry are unlikely to survive. In order to raise a full brood a separate breeding aquarium will have to be used.
Use a long shallow tank with a temp of 27 to 28C  filled with very soft acidic water and filtered with a mature air driven sponge filter. No lighting should be used and the tank should ideally be in shadow.
The floor area should be covered with small pebbles or marbles so that the non-adhesive eggs can fall through and out of reach of the adults. On top of this use bunches of fine leaved plants which the fish will use as a spawning mop.
Place a well conditioned pair in the tank and leave then to settle for a while, then make a small water change using slightly cooler water, this will often trigger spawning.

Remove the parents after spawning and the fry will hatch after 24 to 36 hours depending on the temperature and they will be free swimming after a further 24 to 48 hours. Once free swimming the fry can be fed using a commercial liquid fry food, infusoria or newly hatched brine shrimps.

Wild status

Wild populations of Rasbora kalochroma have not been evaluated but the species is not thought to be vulnerable in the wild.

Additional information

A word of caution, keep clown rasboras well covered as they are good jumpers and sooner or later fish from an uncovered aquarium will be lost.

Information at a glance

pH: 5.5 - 7
dGH: 2 - 7
Temperature: 23 - 28°C (73 - 82°F)
Lighting:
Diet: Omnivore
Size: 10cm (4in)
Min tank size: 250 litres
Difficulty level: Moderate
Aquarium type: Community
Swimming level: All levels

Distribution and habitat

distribution map for Rasbora kalochroma

Origin:  Malay Peninsula and Indonesia (Borneo and Sumatra)

Habitat: Acidic forest streams and swamps.

Classification

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Rasbora
Species: Rasbora kalochroma, (Bleeker, 1851)

Other common names:
None

Synonyms: Rasbora kalachroma,  Leuciscus kalochroma