Blackline Tail Tetra Care Guide
Moenkhausia costae · Freshwater Fish
What Blackline Tail Tetra look like
Moenkhausia costae, commonly known as the Blackline Tail Tetra, exhibits a medium-sized, laterally compressed body that typically reaches a maximum adult size of approximately 3 inches (7.5 cm). The species is characterized by its striking silver body adorned with a prominent dark lateral line that extends into the caudal fin from the caudal peduncle, creating a distinctive visual feature. The scales of this tetra possess a subtle iridescence, enhancing its aesthetic appeal. Sexual dimorphism is minimal; however, females may appear slightly fuller-bodied during the breeding season. Defensive adaptations include a streamlined body shape that aids in quick evasive maneuvers, while the presence of a well-developed adipose fin contributes to stability during swimming. The caudal fin is forked and moderately sized, facilitating agile movements in its natural habitat.
Behavior & temperament
In terms of behavior, Moenkhausia costae is a social species that thrives in small to medium-sized schools, exhibiting a hierarchical structure within these groups. They primarily inhabit the mid to upper water column, displaying a pelagic lifestyle. Breeding behavior involves egg scattering, where females release eggs into the water column, allowing for external fertilization. The Blackline Tail Tetra is generally peaceful and exhibits low aggression levels, making it an ideal candidate for community aquariums. They tend to be more active during twilight hours, showcasing a lively temperament that can be captivating for observers.
Diet & feeding
In the wild, the Blackline Tail Tetra is an omnivore, feeding on a varied diet that includes small invertebrates, plant matter, and detritus. In captivity, they require a balanced diet consisting of high-quality flake foods, supplemented with live or frozen foods such as brine shrimp and daphnia to ensure optimal health and coloration.
Behind the name
The genus name 'Moenkhausia' is derived from the name of the German naturalist and explorer, Hermann Moenkhaus, while the species name 'costae' translates to 'ribs' in Latin, possibly referring to the rib-like appearance of the fish's lateral line.
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Blackline Tail Tetra?
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