Red-Tail Hemiodus Tetra - Hemiodus gracilis
The Redtail Hemi Tetra, also known as the Slender Hemi, is one of the larger sized tetras and can be considered semi-aggressive. They tend to do well with larger fish such as Geophagus, Severums, Angels, etc.
Be sure to have a lid covering the aquarium as they are known to jump.
Size is about 2-3".