Lets learn how to draw a Neon tetra fish in few easy steps. The Neon Tetras are very attractive fish especially when schooled in many numbers in a tank. The attractive part is the red and blue light they seem to emit, which actually is just a reflection.Neon tetras have brightly colored bodies, with a fluorescent blue line along the side. They actually appear to be gleaming in the aquarium, which is why they are called ‘neon’ tetra. Neon tetras must be kept in schools of six or more, and do best in schools of ten or more.