Cochu's Blue Tetra Care Guide
Knodus borki · Freshwater Fish
What Cochu's Blue Tetra look like
Cochu's Blue Tetra, scientifically known as Knodus borki, exhibits a laterally compressed body that reaches a maximum adult size of approximately 2-3 inches (5-7.5 cm). The species is characterized by its semi-transparent body adorned with a striking powder blue to deep violet-blue sheen, which can vary in intensity based on environmental conditions and individual health. Sexual dimorphism is subtle; males tend to display a more vibrant coloration and slightly elongated fins compared to females, which are generally rounder and fuller-bodied, particularly when gravid. Defensive adaptations include a streamlined body that allows for quick evasive maneuvers in the water column, as well as a tendency to school tightly, providing safety in numbers. Unique morphological features include a well-developed adipose fin and a pronounced lateral line system, which aids in the detection of water movements and potential predators.
Behavior & temperament
Cochu's Blue Tetra is a social fish that thrives in small to medium-sized schools, exhibiting a strong tendency to remain in groups for safety and social interaction. They are primarily pelagic, dwelling in the upper to mid-water column of their natural Amazonian habitats. Breeding behavior is characterized as an egg scatterer, where females release eggs in open water, allowing for external fertilization by males. The species is generally peaceful and non-aggressive, making it suitable for community tanks; however, they can display territorial behaviors during breeding periods. Their active swimming patterns and inquisitive nature contribute to their engaging presence in an aquarium setting.
Diet & feeding
In the wild, Cochu's Blue Tetra primarily feeds on small invertebrates, plant matter, and detritus, reflecting their omnivorous diet. In captivity, they thrive on a varied diet that includes high-quality flake food, micro-pellets, and occasional live or frozen foods such as brine shrimp and daphnia to ensure optimal health and coloration.
Behind the name
Knodus (from Greek, meaning 'knot' or 'to tie') and borki (named in honor of the ichthyologist, likely referencing a person associated with the species' discovery or study).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Cochu's Blue Tetra?
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