Learn About Neon tetra - as part of the expert series by GeoBeats. Moving down the line in popularity, next to the Cardinal Tetra, second in line is the Neon Tetra. A fish that looks almost exactly like a Cardinal in the fact, well the only difference being the fact that the red line does not go all the way from the middle of the fish to the nose, it stops at the middle. So it is actually the true U.S.A. fish: It is red, white, and blue. Very, very popular fish, again, a schooling fish, lives in just about any kind of aquarium setting from a large tank and plants to a small tank with not a lot of plants so it does really really well. This fish comes from Peru, and is fairly common all throughout the country there.