Bleeding Blue Tetra Care Guide - Aquarium Setup, Diet & Breeding

The Bleeding Blue Tetra is a small, elegant characin with a silvery to blue-green body that can develop a striking electric-blue sheen under aquarium lighting. Its colour is complemented by reddish markings around the fins and body, giving the species its evocative common name. The intensity of the display varies with mood, condition, sex and the quality of the aquarium environment.

This is a peaceful, active shoaling fish that spends much of its time in the middle levels of the aquarium. In a properly sized group, individuals interact constantly, displaying to one another without usually causing damage. Their coordinated movement and reflective colour make them especially attractive in planted community aquariums.

In nature, Bleeding Blue Tetras inhabit small waterways associated with the extensive Tocantins–Araguaia drainage. These habitats may be bordered by dense vegetation, submerged roots and leaf litter, producing a broken pattern of sunlight and shade. The fish are adapted to gentle-flowing water rather than the turbulence of large rivers.

Hyphessobrycon margitae is less commonly encountered than many of the better-known neon and ember-type tetras, which makes it an appealing choice for aquarists interested in unusual South American species. Its modest size, peaceful temperament and vivid coloration allow it to work well as a focal shoaling fish in a carefully planned community aquarium.

The Bleeding Blue Tetra, Hyphessobrycon margitae, is native to Brazil in the Tocantins–Araguaia basin of South America. It comes from smaller forested streams and tributaries where the water is typically clear to lightly tea-stained and shaded by overhanging vegetation.

A group of Bleeding Blue Tetras should have at least 60 litres, with a footprint of around 60 by 30 cm and a length of 60 cm or more giving them useful swimming space. Use a soft, fine-grained or dark substrate, with dense planting around the sides and back, open water through the centre, and driftwood, roots or leaf litter to provide cover. Gentle filtration, subdued or broken lighting and some floating vegetation help recreate the shaded character of their natural streams while allowing their blue coloration to stand out.

Up to about 3.5 cm (1.4 inches) in total length. Females are usually slightly deeper-bodied and may be marginally larger than males.

Bleeding Blue Tetras are omnivores and should receive a varied diet of quality small flakes or micro-pellets supplemented with frozen or live foods. Daphnia, baby brine shrimp, cyclops and finely chopped bloodworm provide useful variety and help bring out their colour and breeding condition. Offer small portions that the fish can finish quickly, as their small mouths are not suited to large food items.

Bleeding Blue Tetras are peaceful and can be kept with similarly sized, calm community fish such as small rasboras, other gentle tetras, pencilfish, small Corydoras and peaceful dwarf catfish. They may also live alongside non-aggressive ornamental shrimp, although very small shrimplets could be eaten. Avoid large, predatory or boisterous fish, fin-nippers and aggressive cichlids, which may intimidate them or treat them as prey.

Bleeding Blue Tetras are egg-scattering characins that can be bred in a separate, dimly lit spawning aquarium with soft, slightly acidic water and fine-leaved plants or spawning mops. Condition a group with plentiful live or frozen foods, then introduce a male and female or a small group. Spawning usually takes place among the plants, after which the adults should be removed because they may eat the eggs. The eggs hatch in roughly 24 to 36 hours, and the tiny fry can initially be fed infusoria or commercially prepared liquid fry food before progressing to newly hatched brine shrimp.

Males are generally slimmer and often show stronger colour and more extended fin shapes, while females have a fuller belly, especially when carrying eggs. The differences are subtle, and mature females are most readily recognised by their rounder body profile.