Raise live food for them. Baby Brine shrimp will work as already started, but these are expensive IMO and more work than they are worth. Other than that you can feed them vinegar eels(easiest things in the world to raise), Micro worms, grindle worms, and a couple other types of live food. For gouramis vinegar eels would be the best since the eels like to stay near the surface where most of the fry will hang out. For these live foods you will most likely have to order a starter culture on-line.
For the baby brine shrimp, you use your tap water and add salt. Dechlorinate it if you need to, all these foods are disease free.
