Moenkhausia costae (Tetra-Black Line Tail)

The Black Line Tail Tetra (Moenkhausia costae) is a striking and active schooling fish native to the slow-moving rivers and floodplains of South America, particularly the Amazon Basin. Recognisable by the bold black stripe running along its tail and lower caudal fin, this tetra adds both movement and contrast to any community aquarium.

Care & Requirements:

• Size: Up to 5 cm

• Tank Size: Minimum 80 litres, with swimming space and planted areas for cover

• Water Parameters:

  • Temperature: 22–28 °C

  • pH: 6.0–7.5

  • Hardness: 2–12 dGH

• Temperament: Peaceful, ideal for community setups when kept in shoals of at least 6–8

Feeding:

Black Line Tail Tetras are omnivorous and thrive on a varied diet of quality flake or micro pellets, supplemented with frozen or live foods such as daphnia, mosquito larvae, and brine shrimp.

Breeding Tips:

Breeding is possible in a species-only setup. They are egg scatterers with no parental care, so eggs should be protected from being eaten by adults. A separate breeding tank with fine-leaved plants or spawning mops, soft acidic water, and subdued lighting improves success rates. Fry can be raised on infusoria before transitioning to newly hatched brine shrimp or microfoods.

Why Choose Moenkhausia costae?

This underrated tetra is both hardy and attractive, making it a great choice for aquarists who want something different from the more common neon or cardinal tetras. Their lively schooling behaviour and subtle beauty shine best in larger groups.