The emperor tetra is a small fish native to the San Juan and Atrato river basins in Colombia. Wild specimens are not as common as they once were in the aquarium hobby, with the majority of those in the trade produced on a commercial basis. The emperor tetra grows to an adult size of 1.6 inches long. Males are larger, more colorful and develop much more extended dorsal, anal and caudal fins as they mature. It is one of the few species of characin in which the central ray of the caudal fin also becomes elongated. Males also have a blue iris, while females have a green iris.
The emperor tetra should be maintained in an aquarium of 20 gallons or larger. A soft, sandy substrate (CS7581) is probably the best choice. Driftwood (ZM2000) and live plants may also be incorporated.
The emperor tetra prefers a temperature of 73°F to 80°F, a pH of 5.0 to 7.5, and a hardness of 18 to 215°H.
The emperor tetra is an excellent fish for a community aquarium as it is lively and peaceful. Keep it in groups of 6 or more for the best effect. Good tank mates include livebearers, danios, rasboras, dwarf gouramis, cory catfish, smaller Loricariids, other tetras, pencil fish, and peaceful dwarf cichlids.
In the wild, the emperor tetra is a micropredator primarily feeding on aquatic insect larvae, worms, and tiny crustaceans. In the aquarium it will accept dry and frozen foods of similar sizes. Good choices include frozen bloodworm (SF4792) and cyclops, as well as high quality flakes (AL165). For maximum color, growth, and health these fish will look their best when given probiotics (AL169) in addition to a balanced diet.