Rasbora Kalochroma (Clown Rasbora)

Aquarium Livestock
17 Nov 00:00

Clown Rasbora

Common names: Clown Rasbora / Big Spot Rasbora

Scientific name: Rasbora Kalochroma

A really special rasbora and a great fish for the larger community aquarium. It is a medium size shoaling fish that can also be kept with smaller species as it is very peaceful.

When in good condition they are a striking pinkish red colour, they cruise around the top third of the aquarium and shoal together really well, making a different addition to the aquarium.


Sexing:  The females are slightly larger and more rounded in the body.

Size: 10cm.

Where are they from?: Malaysia, Borneo and Sumatra.

Habitats: Their natural habitats are generally peat swamps. The water is very soft and acidic with the pH as low as 4!

Aquarium size: Minimum 100cm x 40cm x 40cm.

Aquarium conditions: A quiet aquarium is best – they are quite active but are not boisterous at all, so will appreciate relaxed tank mates. Ideally the water will be pH 7 or lower, although they can be kept successfully in harder water in mature aquariums.

Some people recommend they are kept in pairs, this is ok, but really they love to shoal and will do so if a good size group is kept. Ideal tank mates would be other fish from southeast Asia such as rasboras and smaller barb species (would look great with the 5 banded barb). They will also mix with other peaceful species like tetras.

They look nice in many setups, but do look best when in a biotope aquarium mimicking the swamp areas they come from with bogwood and water that is coloured brown by tannins. The substrate could be sandy, with scattered pebbles and almond leaves. Kept in this way, their colour and pattern will look outstanding. They also look amazing in larger planted aquariums.


Egg scattering spawners, Clown Rasboras will require soft, acidic water in order for their eggs to hatch. They are not bred very often (mainly because they are fairly rarely kept), a bit of practice with other rasbora species first would probably help.

They are best spawned in a separate breeding aquarium set up specifically for this purpose.

Final comments / Key points

  • Just amazing, spotty, red, torpedo-shaped fish, a pleasure to keep.
  • Will be wild caught fish. Notoriously sensitive as new imports, so do talk to your supplier and only buy fish that are fully quarantined and acclimated to your local water.
  • Must be kept in a mature aquarium that has been set up for at least 3 months.
  • Prone to white spot when stressed, so always look at the fish carefully in the shop and ask them how long they have been in, maybe reserve some if they are a new arrival.

Author & Photo credit - Parkers Manager Patrick Davies.