The Buenos Aires Tetra (*Hyphessobrycon anisitsi*) is one of the hardiest and most active tetras in the aquarium hobby. Originally from the cooler river systems of South America (Argentina, Brazil, and Paraguay), it is significantly more temperature-tolerant than many other tropical species. My father-in-law acquired a school of these when converting his 720-liter tank from Malawis to a community setup.
While they are beautiful with their reddish fins and distinct black spot at the tail base, they have a reputation for being somewhat troublesome. As they mature, they become increasingly dominant and voracious. They are notorious fin-nippers, especially toward slow-moving tank mates with flowing fins. Furthermore, they are well-known plant-eaters and can quickly decimate delicate flora. If kept in a planted tank, it is best to choose hardy species like Anubias or Java ferns and supplement their diet with plenty of vegetable matter.
To truly enjoy their spirited swimming and vibrant colors, they are best kept in a species-only tank or with other fast, robust companions. Although they are prolific egg scatterers, their boisterous temperament makes them a specialized choice for the community aquarium.
