Cochu’s Blue Tetra Care Guide - Aquarium Setup, Diet & Breeding

Cochu’s Blue Tetra is a slender, lively characin with a vivid blue-green sheen that can appear almost electric when the fish turns in the light. Its body is mostly translucent silver-blue, with subtle yellowish tones around the fins and a dark eye that adds definition to its bright appearance.

This is an active midwater fish that spends much of its time moving through open water in a coordinated group. It is generally peaceful, although individuals can become boisterous and may show occasional fin-nipping behaviour when kept in an undersized group or a cramped aquarium.

In the wild, these tetras inhabit warm, flowing freshwater environments in the Amazon region. Their natural surroundings may include overhanging vegetation, submerged roots and areas of broken shade, which help explain their confidence in a planted, visually complex setting.

Boehlkea fredcochui was named in honour of Fred Cochu, a collector and importer associated with the aquarium trade. Its sparkling colour, constant movement and relatively modest adult size have made it a popular choice for peaceful tropical community aquariums.

Cochu’s Blue Tetra is native to the upper Amazon region of Peru in South America. It occurs in tropical freshwater streams and tributaries associated with the Amazon basin.

A group should be kept in an aquarium of at least 60 litres, with a footprint of approximately 60 × 30 cm or larger. Use open swimming space across the middle of the tank alongside dense planting, fine-leaved vegetation, floating plants, roots and subdued areas of shade. A dark, fine-grained substrate can enhance their colour, while gentle water movement and clear, well-maintained water suit their active nature.

Males reach about 4 cm (1.6 inches), while females can grow to approximately 5 cm (2 inches) in total length.

These omnivorous tetras accept quality small flakes, micro-pellets and granules, supplemented with frozen or live foods such as daphnia, mosquito larvae and brine shrimp. Offering small portions several times a day helps ensure that all fish receive food, while occasional vegetable-based ingredients can provide useful variety.

Cochu’s Blue Tetras are suitable for peaceful community aquariums with similarly sized tetras, rasboras, danios, small peaceful barbs, Corydoras and other calm South American community fish. They can also live with peaceful dwarf cichlids and smaller bottom-dwelling catfish when the aquarium is spacious enough. Avoid large predatory fish, aggressive species and slow, long-finned fish that may be stressed or nipped by an active group.

Cochu’s Blue Tetras are egg-scattering spawners that can be bred in a separate, dimly lit breeding aquarium with soft, slightly acidic water and fine-leaved plants or spawning mops. Condition a group with plentiful live or frozen foods, then introduce the adults when females are full of eggs. Spawning usually occurs among the plants, after which the adults should be removed because they may eat the eggs. The eggs hatch in roughly a day, and the fry become free-swimming a few days later; feed them infusoria or another suitably tiny first food before moving on to newly hatched brine shrimp.

Females are usually slightly larger and deeper-bodied, particularly when carrying eggs. Males tend to be slimmer and may show a more intense, streamlined blue sheen, although the differences are modest and can be difficult to judge in young fish.