Name: Cardinal TetraScientific Name: Paracheirodon axelrodiMaximum Length: 2.0 inches (5.1 cm)Favorite Things: Large schools with their own kind, heavily planted aquariums, soft acidic water, and small live or frozen foods such as daphnia and brine shrimpBest Buddies: Peaceful community fish like Corydoras catfish, small rasboras, and other non-aggressive tetras How They Differ From Neon Tetras:Cardinal Tetras look very similar to Neon Tetras, but their red coloration runs the entire length of the body—from the midsection through the tail—while Neon Tetras only have red on the back half. Cardinals also tend to prefer slightly warmer water and are considered a bit more delicate to keep, but their full-length red stripe makes them more vivid and striking in planted aquariums.