Glowlight tetras (Hemigrammus erythrozonus) are from the Essiquibo basin in South America. They are small, peaceful fish that only reach a maximum size of about 1.5 inches (4 cm). Like the other tetras (e.g., cardinal, neon) they belong to the family Characidae.
The common name glowlight tetra is derived from the horizontal red stripe that extends from their midbody to the base of their tail. This stripe "glows" under the aquarium lights.
Glowlight tetras are shoaling fish that can easily be kept in a community tank as long as you don't keep them with other large or aggressive species. Because glowlights are shoaling fish you need to keep at least 4-6 glowlight tetras in your aquarium, otherwise they won't be happy fish.
Like most of the tetras they prefer soft, slightly acidic water (pH of 6.8), and a water temperature between 75-83 °F or 24-28 °C.
You should keep them in a well-planted aquarium. It is best to have the plants located at the sides and back of the tank so that they have plenty of swimming room.
They will eat flakes, frozen, freeze-dried, and live foods.
They are egglaying fish and will breed in the aquarium providing that the water conditions are right. Males and females are identical in coloration, but you can usually tell the females from the males because the males have a more slender body. This is because an adult female will be full of eggs.
To breed glowlight tetras put the breeding pair in a separate breeding tank. It is best to filter their water through peat. You should also provide plants in their tank, such as hornwort or other aquatic plants with fine leaves. During spawning they will scatter their eggs among the plants. Once spawning is complete remove the breeding pair or they will eat the eggs.
The fry will hatch in about 24 hours. They fry of tetras are generally very tiny. When the fry are free-swimming feed them liquid fry food for egglaying fish, infusoria, and rotifers. When the fry grow a little larger feed them newly hatched brine shrimp and powdered fish food for fry.