Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Hemigrammus erythrozonus

Glowlight tetra

Glowlight tetra, Hemigrammus erythrozonusGlowlight tetra, Hemigrammus erythrozonus
Photos by Andy Rapson


Hemigrammus: Greek, hemi = half + Greek, gramma = letter, signal.

General Notes:

Glowlight tetras are reliably peaceful and undemanding community fish. They do much better, look better and behave more naturally when kept in a shoal of at least five with their own kind. Ideally their water should be soft and acidic but they will thrive as long as extremes are avoided. There is an albino form of glowlight tetra available now too. Glowlight tetras are one of the best community fish for a new fish keeper to begin with. They are generally very peaceful, undemanding, colourful and hardy.


In the wild Hemigrammus erythrozonus feeds on insect larva, crustaceans and worms. In captivity they will accept flake food, appropriately sized live or frozen food and freeze dried food.


As with lots of other small tetras the females of Hemigrammus erythrozonus are slightly larger and more rounded than the males. The males are also slightly more colourful.


Hemigrammus erythrozonus are egg scatterers. The female lays semi adhesive eggs as the male chases here through some aquatic plants which are fertilised at the same time. Neither parent cares for the brood after spawning and they may even prey on their own eggs. Glowlight tetras are one of the easier characins to breed and if well cared for they will spawn quite routinely in a community tank though it is unlikely that any fry would survive in that situation.

Wild status

The health of wild populations have not been evaluated but all aquarium specimens are likely to be captive bred and so the aquarium trade has little or no impact on wild populations.

Information at a glance

pH: 6 - 7.5
dGH: 4 - 15
Temperature: 24 - 28°C (75 - 82°F)
Diet: Omnivore
Size: 4cm (1.7in)
Min tank size: 60 litres
Difficulty level: Easy
Aquarium type: Community
Swimming level: All levels

Distribution and habitat

distribution map for Glowlight tetra, Hemigrammus erythrozonus

Origin: South America, Guyana, Essequibo River.

Habitat: Black water forest streams.


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Characiformes
Family: Characidae
Genus: Hemigrammus
Species: H. erythrozonusa

Common name:
Glowlight tetra

Synonyms: None