The title is the tough question for me to figure out. Right now I have a happy community with space left over in my tank to add a few more more. Currently living happily are 5 Black Skirt Tetra, 6 Red Minor Serpae, 3 White Fin Rosy (that was all they had left but they school with both my Red's and my Black Skirts) and 1 Dwarf Gourami who thinks he is a Tetra. I am looking at adding another small school of 5 or 6 fish that will add some color to the tank and get along well with the other inhabitants. Or possibly a couple of singles that will get along and bring some brightness as well. Maybe something with some blues or yellows. Any suggestions to help finish off this happy home?