Cardinal Tetra
Paracheirodon axelrodi
The cardinal tetra (Paracheirodon axelrodi) is a small schooling characin from blackwater and clearwater tributaries of the upper Rio Negro and Orinoco regions. It is famous in aquariums for the electric blue stripe above a red stripe that runs nearly the full length of the body, distinguishing it from the shorter red of the neon tetra. In the wild, cardinal tetras live in shaded, acidic, soft waters among roots, leaf litter, and flooded forest margins, feeding on tiny invertebrates and planktonic foods.
Aquarium cardinal tetras do best in groups large enough to feel secure, with stable warm water, gentle flow, subdued lighting, and peaceful tankmates that will not treat them as food. They accept fine prepared foods, frozen microfoods, and small live foods, but sudden water changes and poor quarantine can lead to losses. Many are wild collected through fisheries that can support local communities when managed responsibly, while captive-bred fish are also available. Buyers should look for full color, rounded bodies, and active schooling before adding them to a mature tank.
