Glowlight rasbora
Trigonostigma hengeli
Also known as Narrow Wedge Rasbora
FreshwaterFish
Care at a glance
- Temperature
- 73–82°F
- 23–28°C
- pH
- 6.0–7.0
- Adult size
- 1.6 in
- 4 cm
- Minimum tank
- 12 gal
- 45 L
- Temperament
- Peaceful
- Social behavior
- Schooling
- Swim level
- Middle
- Difficulty
- Easy
- Breeding
- Medium
- Rarity
- Rare
- Family
- Cyprinidae
- Origin
- Sumatra, Borneo
Overview
Glowlight rasboras are tiny, peaceful shoaling fish that should be kept in a group of at least eight to ten, since a good sized shoal keeps them bold and shows off their glowing color. They occupy the middle water and drift together in gentle, open swimming areas among plants. Their small size and calm nature make them perfect for a planted nano or a quiet community, but they must not share a tank with anything large enough to eat them or boisterous enough to bully them. Feed small foods such as fine flake, crushed micro pellets, and tiny frozen or live items like cyclops and baby brine shrimp. A tank around 45 liters or larger will comfortably hold a shoal of these little fish.
In the wild
This rasbora comes from the soft, acidic blackwater streams and peat swamp forests of Sumatra and Borneo, where the water is warm, dark, and stained with tannins. It shows best in warm water of about 23–28 C and an acidic pH of 6.0–7.0. Set that up with a dark base, driftwood, and leaf litter, with dense planting around open swimming space. Soft, tannin stained water under gentle, subdued lighting brings out the bright copper band that gives the fish its name.
Good to know
Trigonostigma hengeli is a small member of the family Cyprinidae, reaching only about 4 cm. It is a slender relative of the harlequin rasbora, carrying a black wedge along the rear body that is topped by a striking, almost fluorescent orange stripe. It is an egg depositing spawner that lays its eggs on the underside of broad leaves rather than simply scattering them, and it can be bred in soft, warm water with moderate effort.
Did you know
The glowlight rasbora is easily confused with two close relatives, the lambchop rasbora and the larger harlequin rasbora. Hengel's fish is the slimmest of the three, with the narrowest black marking and the brightest band of orange sitting just above it.
Weekly picks
Tank mates
Glowlight rasbora is a peaceful, schooling species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Honey blue-eye
Pseudomugil mellis
Freshwater1.4 in (3.5 cm) · 11 gal (40 L)68–82°F (20–28°C)
Bamboo shrimp
Atyopsis moluccensis
Freshwater3.9 in (10 cm) · 13 gal (50 L)72–84°F (22–29°C)
Hercules snail
Brotia herculea
Freshwater3.1 in (8 cm) · 11 gal (40 L)73–82°F (23–28°C)
Dwarf cory
Gastrodermus hastatus
Freshwater1.3 in (3.2 cm) · 12 gal (45 L)68–79°F (20–26°C)
Blue axelrodi rasbora
Sundadanio axelrodi
Freshwater0.8 in (2 cm) · 12 gal (45 L)73–79°F (23–26°C)
Green panchax
Aplocheilus blockii
Freshwater2 in (5 cm) · 11 gal (40 L)72–82°F (22–28°C)
Common questions
What size tank does a Glowlight rasbora need?
A Glowlight rasbora needs at least 12 gal (45 L). It spends most of its time in the middle.
What temperature and pH does a Glowlight rasbora need?
A Glowlight rasbora is comfortable at 73–82°F (23–28°C) with a pH of 6.0–7.0.
How big does a Glowlight rasbora get?
An adult Glowlight rasbora reaches about 1.6 in (4 cm).
Does a Glowlight rasbora need a group?
Yes. A Glowlight rasbora is a schooling species and should be kept in a group, not singly.
Related species
1.5 in (3.8 cm)11 gal (40 L)73–82°F (23–28°C)Espei rasbora
Trigonostigma espei
1.5 in (3.8 cm) · 11 gal (40 L)
2 in (5 cm)15 gal (55 L)72–82°F (22–28°C)Harlequin rasbora
Trigonostigma heteromorpha
2 in (5 cm) · 15 gal (55 L)
1 in (2.5 cm)12 gal (45 L)73–81°F (23–27°C)Somphongs's rasbora
Trigonostigma somphongsi
1 in (2.5 cm) · 12 gal (45 L)
1.6 in (4 cm)20 gal (75 L)68–79°F (20–26°C)Canius barb
Pethia canius
1.6 in (4 cm) · 20 gal (75 L)
1.6 in (4 cm)14 gal (54 L)73–82°F (23–28°C)Drape-fin barb
Oreichthys crenuchoides
1.6 in (4 cm) · 14 gal (54 L)
1.6 in (4 cm)14 gal (54 L)73–81°F (23–27°C)False eight-banded barb
Eirmotus octozona
1.6 in (4 cm) · 14 gal (54 L)
