• Scientific name: Trigonostigma hengeli
• Synonyms: Rasbora hengeli (Meinken, 1956)
• Common name: Hengel Rasbora, Glowlight rasbora
• Group: Cyprinids
• Habitat: Southeast Asia; Sumatra and Borneo, Indonesia
• Size: 2.5-3 cm
• Biotope: Found in slow-flowing parts of forest streams with dense vegetation. These black water streams are often brown colored due the decomposing organic matter and the lots of dried leaves. These waters are typically soft and weakly acidic.
• Social behavior: A very peaceful, schooling fish, which can be kept with other fish, prefering similar conditions. It is important to keep at least 8-10 species in a group.
• Diet: Omnivorous; In nature they feed on small insects, worms, and zooplankton. In the aquarium they can be fed with live, frozen and flake foods too.
• Breeding: Hard
• Tank: Minimum 40 litres
• Population: 8-10 fishes for 60 litres
• Decoration: They look best in a heavily-planted tank, with dark substrate. Decorate the tank with some floating plants, driftwood and roots. Use subdued lighting, and place some dried leaves into the tank to provide more natural environment.
• Temperature: 23-28 °C
• pH: 5-7
• Hardness: 1-10 NK°
• Lifespan: 4-6 years

Description: Hengel Rasbora can be confused with their similar-looking close relatives, but Trigonostigma heteromorpha (Harlequin rasbora) has a broader, characteristic black body marking, while the other similar fish Trigonostigma espei has a bright yellowish-reddish body color without the orange stripe above the black triangle. Trigonostigma hengeli has an overall greyish-green colored body with a bright orange stripe just above and beside the thin black marking along the back half of the body. Their fins are faint yellowish. Hengel Rasbora is a very hardy fish, it is an ideal fish for beginners.

It is quite hard to tell apart the sexes, mature females are usually rounder-bellied and often a little larger than the more intensely-coloured males. Trigonostigma hengeli deposit the eggs to the underside of broad plant leaves or other objects rather than scattered randomly in the aquarium as other cyprinids do, however they exhibiting no parental care at all. Well-fed fish will usually spawn, and it is possible that a small numbers of fry will survive in the community tank, however if you want to save more fry, a separated aquarium is required. They can be bred in a small, dimly lighted tank, that filled with slightly acidic (pH: 5-6), very soft (1-3 NK°) water, and have a few broad-leaved plant in it. Some breeders report that one year old or older fish are a little easier to breed, as it is harder to initiate spawning behaviour in younger fish. Condition the adult fish for a couple of days with live foods, and place them into the breeding tank. After this, do a larger water change with a little cooler water. The fish will usually spawn in the following morning. If the pair fail to spawn after 3 or 4 days, then a different pair should be chosen. After spawning the adult fish should be removed from the tank, as they will eat the eggs. The eggs hatch in 24-48 hours which is temperature-dependant, and the fry become free-swimming after a week. The fry should be fed with very small live foods.