The VON RIO ORANGE TETRA is one of the most entrancingly beautiful of all aquarium fish, especially when it is in its full breeding colors. At one time, almost no community aquarium was complete without this fish. In the 1940s and 1950s, it was among the best sellers of all characins. One reason for its overwhelming popularity was the ability to survive in a wide temperature range. Before the days of affordable heating for the home aquarium, this went a long way towards making it the first choice as a first fish.