At a glance the quick version
Looks how to spot one
Slender, scaled cyprinid with a forked tail
A larger rasbora with a pinkish to deep red body. Two dark blotches sit on each flank, one just behind the gill cover and a bigger one in the middle of the body, and their exact shape varies between wild populations. Males tend to be slimmer and brighter, while mature females are larger and rounder.13
Personality what they are like
Calm and gentle, but a little shy until it is kept in a proper group. In a settled shoal the males show off their colours to one another, which makes for a lively display.1
Daily activity how busy a day looks
An active swimmer that needs open water along the length of a roomy tank. It is a capable jumper, so a well-fitting lid is important.1
Grooming and care the hands-on bits
Does best in a mature, stable aquarium rather than a newly set up one. Steady water chemistry, regular partial water changes and a tight cover keep it comfortable.1
Home where they are happiest
Soft, acidic to neutral water at about 23 to 28 C, pH roughly 5.0 to 7.5 and hardness 2 to 10 dGH. A base of at least 120 x 45 cm (about 240 litres) suits a group. Dim light, leaf litter, wood and tannin-stained water echo its swamp home and bring out its colour.12
Food basics what goes in the bowl
In nature it eats small aquatic and land insects and other invertebrates. In the aquarium it takes good flakes and granules, best mixed with live or frozen bloodworm, Daphnia and brine shrimp.12
Company who they like around
A schooling fish that should live in a group of at least 8 to 10. Fits well with other peaceful fish of similar size.1
The story where it all began
First described by Bleeker in 1851 under the name Leuciscus kalochroma and later placed in Rasbora. Its home is the ancient peat swamp forests of Malaysia, Sumatra and Borneo, where tannins stain the water dark. Very similar relatives include Rasbora kottelati, which has an extra spot near the tail.31
Fun facts for the dinner table
- 1
At around 10 cm it is one of the larger rasboras kept in home aquariums.2
- 2
Its wild home can be as acidic as pH 4, coloured dark by tannins from fallen leaves.1
- 3
The size and shape of its dark side spots differ from one locality to another.1
- 4
It scatters its eggs among plants and gives no parental care; in a mature planted tank some fry may grow up unaided.1
Recognised by the official bits
- IUCN Red List
- Least Concern (assessed August 2019)2
- FishBase
- Listed as a species used in the aquarium trade2
The care rhythm Furry Diary remembers it for you
A typical home-care rhythm for a Clown Rasbora. It is our own starting plan, not a vet's advice, and you can change every line in the app.
- FeedingSmall amounts once or twice a dayevery day
- Temperature checkevery day
- Water changeAbout 25% of the waterevery week
- Water testevery week
- Glass cleanevery week
- Filter rinseRinse in old tank water, never tap waterevery month
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Where this comes from
Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at [email protected] and we will fix it.
- Rasbora kalochroma (Clown Rasbora), Seriously Fish seriouslyfish.comused for origin, habitat, size, water parameters, tank size, diet, behaviour, fun facts
- Rasbora kalochroma, FishBase fishbase.seused for max length, IUCN status, distribution, temperature
- Clown rasbora, Wikipedia en.wikipedia.orgused for colours, former name, history
Checked 2026-09-30. Text is written in our own words from these sources.