Bass Tetra

Geographic Origin and Biotope: Very widespread species: from the Orinoco basin to the Amazon down to the Paraná and Paraguay basins in Argentina. Inhabits countless habitats but prefers clear forest streams and slow-flowing rivers with abundant vegetation.

Taxonomy and Morphology: Bass Tetra / Marginated Tetra (Hemigrammus marginatus). The name "marginatus" refers to the distinctive chromatic margins of its fins. Features the silvery-green body characteristic of the group.

Social Behavior: Schooling characin, peaceful but very dynamic. Interacts elaborately within the school, with continuous displays among males that never result in physical harm. Must be strictly kept in schools of at least 10 specimens.

Coloration and Sexual Dimorphism: Sparkling silvery and greenish livery. Distinguished by a broad green-gold horizontal stripe and a beautiful caudal fin: central black spot bordered above and below by bright yellow/white spots. Females have a more curved belly.

Aquarium Setup: Tank of at least 80 cm (32 inches), densely planted on the sides and bottom (Echinodorus, Vallisneria), leaving the central swimming space open. A dark bottom will enormously highlight the color contrast of the fins.

Diet and Feeding: Undemanding. Avidly accepts flakes, micro-pellets, but to maintain high immune levels it is good to administer daphnia, cyclops, artemia (live or frozen) at least twice a week.

Water Quality: Very robust fish thanks to its wide geographic distribution. Tolerates a wide range of hardness and temperatures (22-28°C / 72-82°F), but hates ammonia accumulations or immature filters. Appreciates a moderate current.

Compatibility and Tankmates: Exceptional tankmate for almost all South American community tanks of appropriate size. Perfect with Corydoras, Ancistrus, and dwarf Cichlids (Apistogramma). Not to be mixed with medium-large Cichlids that will prey on it.

Aquarium Reproduction: Easy to achieve in dedicated tanks with soft and weakly acidic water. They lay dozens of eggs scattering them in mosses or on synthetic mops. Breeders must be removed quickly to save the offspring.

Risks and Diseases: Rarely subject to diseases if kept under stable conditions. Introduction into tanks with immature filters or ammonia spikes causes rapid fin deterioration (Fin rot) and asphyxiation.