The Cardinal Tetra brings delicate beauty to any home freshwater aquarium. It has a bright blue stripe contrasted by a lower red stripe that runs the entire length of its body. This coloration differs from its cousin, the Neon Tetra, which has a red stripe that runs only halfway down the body. Equally as peaceful as Neon Tetras, Paracheirodon axelrodi will school together for a brilliant display of activity and color to dress small to large aquarium systems.Native to the slow moving waters of the various, well-vegetated tributaries in South America, the Cardinal Tetra needs at least a 10-gallon aquarium that is densely planted with areas of low or subdued lighting. Though relatively hardy, the Cardinal Tetra does best in soft, acidic water with few fluctuations in water parameters. The Cardinal Tetra should be kept in groups of six or more and be housed with equally peaceful tankmates.