It's a lot of work to maintain good water in a small, overstocked tank, so maybe do just one "showy", colorful school of fish and make it a little bigger i.e. 6 tetras or 6 platys, with the 1 dwarf gourami and a small school of 3-4 corys. All your water levels are covered, your fish will be happier with the bigger school size, and you won't be quite so overstocked. :thumbsup:
Better.what about 4 black phantom tetras instead of black skirts?