Harlequin Rasbora

Trigonostigma heteromorpha

Copper-orange with a signature black "pork chop" patch. Harlequins school tightly and look spectacular in planted tanks.

A peaceful freshwater fish that grows to 4.5 cm, lives in the middle of the tank in groups of 6 or more and needs 22–28 °C, pH 5.5–7.5 and an aquarium of at least 40 L.

Care at a glance

Water

Freshwater

Temperature

22–28 °C (72–82 °F)

pH

5.5–7.5

Adult size

4.5 cm (1.8 in)

Aquarium

40 L or bigger (11 US gal)

Temperament

Peaceful

Group size

6 or more

Swims

Middle

Diet

Omnivore

Wild home

Peat swamps of Malaysia & Sumatra

Tank mates

Good company: Amano Shrimp, Bristlenose Pleco, Corydoras, Dwarf Gourami, Ghost Shrimp, Honey Gourami, Kuhli Loach, Marbled Hatchetfish, Mystery Snail, Neocaridina Shrimp.

Eaten by: Asian Arowana, Axolotl, Black Ghost Knifefish, Flowerhorn, Frontosa, Jack Dempsey, Motoro Stingray, Ornate Bichir, Oscar, Siamese Tigerfish.

Attacked by: Demasoni Cichlid, Flowerhorn, Jack Dempsey.

Eats the newborn fry of: Cardinal Tetra, Celestial Pearl Danio, Cherry Barb, Chili Rasbora, Crystal Red Shrimp, Ember Tetra, Endler's Livebearer, Ghost Shrimp, Glowlight Tetra, Honey Gourami, Neocaridina Shrimp, Neon Tetra and 5 more.

Its fry are eaten by: Angelfish, Bala Shark, Betta, Black Skirt Tetra, Bloodfin Tetra, Boesemani Rainbowfish, Cherry Barb, Clown Loach, Cockatoo Dwarf Cichlid, Comet Goldfish, Congo Tetra, Discus and 24 more.

Grown ones eat their own newborn fry, so raise the young in another aquarium.

Colours and breeding

• Classic common

In Aquarius a grown male and female breed in a healthy tank. Their young are born about 0.3 cm long and take after one of the parents.

The care values are the ones Aquarius uses, based on how these animals live. Tank mates follow the game's rules: water type, temperature and pH, who can swallow whom, fin nipping, temperament and territory.