Harlequin rasbora
Trigonostigma heteromorpha · Danionidae
Also known as Red rasbora
Beginner
Copper body with a black wedge; forgiving, peaceful and happiest in a tight group.
In short: A harlequin rasbora needs at least 60 L (16 US gal), water at 22–28 °C (72–82 °F) and pH 5.5–7.5. It is peaceful, best kept in groups of 8 or more, and rated beginner to keep.
- Minimum tank
- 60 L (16 US gal)
- Temperature
- 22–28 °C (72–82 °F)
- pH
- 5.5–7.5
- Adult size
- 4.5 cm (1.8 in)
- Group size
- 8+
Care requirements
- Minimum tank volume
- 60 L (16 US gal)
- Temperature
- 22–28 °C (72–82 °F)
- pH
- 5.5–7.5
- Hardness
- 2–15 dGH
- Lifespan
- 4–8 years
- Diet
- Omnivore — flake, micro pellets, frozen daphnia.
- Care level
- Beginner
Origin & habitat
- Native region
- Malaysia, Sumatra, southern Thailand
- Water type
- Freshwater
- Biotope
- Peat swamp forests and blackwater streams
- Natural conditions
- Soft, acidic, tannin-rich water with dense plants.
Behaviour & stocking
- Temperament
- Peaceful
- Minimum group
- 8 fish
- Swims
- Mid-water
- Good tank mates
- CorydorasNeon tetraHoney gouramiOtocinclus
- Avoid
- Large cichlidsAggressive barbs
Breeding & difficulty
- Breeding difficulty
- Advanced
- Sexing
- Males have a sharper, extended black wedge.
- Notes
- Deposits eggs on the underside of broad leaves in very soft water.
- Common ailments
- IchVelvet
Will it fit your tank?
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