All fish / Danionidae

Somphong's Rasbora

Trigonostigma somphongsi

Also known as somphong's rasbora, somphongsi rasbora, somphong rasbora, somphong's harlequin, rasbora somphongsi, dwarf harlequin rasbora, ปลาซิวสมพงษ์, ラスボラ・ソムフォンシー, 桑氏三角灯

This is a slim, small relative of the harlequin rasbora. It has a pinkish orange body with a thin black stripe running back from mid-body towards the tail. Keepers value it as a rare, peaceful nano fish for planted, soft water tanks.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

2.5 cm

Temperature

22 to 27 °C

pH

5.5 to 7

Smallest tank

40 litres

Keep as

Shoal of 10 or more

Diet

Omnivore: small live and frozen foods such as daphnia and baby brine shrimp, plus fine flake

Swims

Middle of the tank

Lifespan

3 to 5 years

Water

Freshwater

Wild range

Thailand (Mae Klong basin)

Breeding

It scatters eggs and lays them on the undersides of broad leaves, much like the harlequin rasbora. Spawning in captivity is possible in soft, acidic water, but fry numbers are usually low.

Good to know

It is critically endangered in the wild and was once thought to be extinct, so buy captive-bred stock where you can. It can be confused with Trigonostigma espei and T. hengeli, which both have a larger black wedge marking.