The Paraguay Tetra is characterised by having two black marks on the caudal peduncle and anal fin, with three contrasting white spots. This striking pattern is best displayed in a tank with plenty of green plants and dark gravel. They grow to a maximum size of approximately 4cm and have a relatively peaceful nature, similar to most tetras of this size.
Tetras are considered easy to keep in a community aquarium of at least 20L, with a pH of 5.07.0 and KH of 1.02.0. However, they will not tolerate dramatic changes to their environment. The Tetra can live 10 years or more with the proper conditions. They tend to be timid and, because of their small size, should not be kept with large or aggressive fish who may bully or simply eat them.
Fish that mix well in an aquarium are other types of tetras, and other community fish that live well in an ideal Tetra water condition. Mid-level feeders, they are best kept in schools of five to eight or more, for the "shoaling" effect when they move around the tank. They shoal naturally in the wild and are thus happier, more brightly coloured, and more active when kept as a shoal as opposed to singly.
Tetras are best kept in a densely planted tank with subdued light and an ideal temperature of 2024?C to resemble their native Amazon environment. Tetras are omnivores and will accept most flake foods, but should also have some small foods such as brine shrimp, daphnia, freeze-dried bloodworms, tubifex, and micro pellet food to supplement their diet.