What is the best food for tropical freshwater fish ...

if you are trying to breed them live food is best, frozen if you don't have access to live.  if you are just adding them to your community tank most any flake food is good.  imagine how small their stomachs are and don't over feed.

Here is a great article on feeding freshwater fish. Hope that it helps.

variety!!!  live brown worms, live brine shrimp and the best quality dried fish flakes.  both types of fishes you describe are omnivores (they eat anything and everything fishes)  temp. is important, 85F for 6 months then slowly 78F for another 6.  hot season and a cooler season.  peat moss in the tank will color the water a golden tea color and acidify and soften the water.  the fishes colors will astound you and they may spawn.  10% water changes weekly at 78 and 5% weekly at 85.  think Amazon and Indonesia... my favorite... Moen tetras (red eyed tetras) cardinals also!  great luck to you from Sparklesquid in Portland

frezze dried fish flakes are the best type of food for tropical fish

Freeze Dried Tubifex Worms is a really great food source for your fresh water fish.

I also recommend changing the the foods to stimulate feeding which help in growth of your fish and coloration of the male species.