Moenkhausia sanctaefilomenae is a mid sized tetra from South America that reaches about 2.5" in length. Although they have a reputation as fin-nippers, a larger school (6-8 individuals or more) usually keeps that aggression contained to themselves. That being said, they are quite active and may intimidate shy fish as dwarf cichlids or small gouramis. These subtle yet pleasing fish add lots of activity to any community aquarium.
These are adults around 1.5" long.