Semaprochilodus insignis is a large, splendid characin from South America. Prochilodus are important food fish where they come from, but it is largely only this species that is imported for the aquarium trade. Reaching around 14", these are no small schooling fish. They are peaceful with other large fishes and make a good dither for monster fish. You may either keep one singly, or a large group (6 ), as they are somewhat aggressive with each other in smaller numbers.