Tropical

Glowlight Tetra

The glowlight tetra (Hemigrammus erythrozonus) is so-called because of the striking red stripe which runs down each side of its body, from nose to tail. It grows to about 3.75cm (1.5in) long. A colour variant, with an orange rather than red stripe is also now seen quite regularly.

Glowlight tetraThe Esequibo River in Guyana, South America is the original home of this pretty tropical fish, which was first introduced to the aquarium hobby in 1933. Today, these tetras are now being bred in many countries around the world, and have become one of the most widely-kept members of the group.   

They will live together in small shoals in a community aquarium, where the water is soft, and slightly acidic. The aquarium should be well-planted, and the lighting needs to be diffuse. This can be achieved by adding floating plants on the surface of the aquarium, allowing a suitable gap beneath the hood.

Feeding is very straightforward, with flake food, offered in small quantities serving as a good basic diet for these tetras. As the time for spawning approaches, so the female is likely to swell with eggs, and this is the easiest way of distinguishing between the sexes. A separate spawning tank will be needed, because the adult fish will otherwise eat their eggs and any fry which do hatch.

Spawning will take place in among the plants, with the eggs hatching just over a day later. The fry will then remain inert for another four or five days, until they have digested their yolk sacs, when they become free-swimming and start to search for tiny particles of food.  The young tetras grow fast, and are easy to rear in a spacious aquarium on commercial diets. 

Photo courtesy: gonzalovalenzuela