Just saw this....but, will add my 2 cents. If you are going to raise baby fish in an aquarium, if you have totally clean, clear water, there is nothing in there for them to eat. Even pulverized flake food is not very good. Make sure you are not putting more fish than your container/aquarium can manage. If the water has a slightly green tint to it, all the better, because the microscopic algae is a food for them too. Use an airstone or a sponge filter. Take a boiled egg yolk and stir some into a little water and drop a little in there...but only a little bit because it will easily foul the water.
Put a light at one end of the aquarium...the baby fish will congregate there. Turn down the air so the water isn't turbulent and knocking them about. If you hatch baby brine shrimp, they will also be attracted to the light.
An easier way is to take a tub, fill with pond water, put in some plants and some fish eggs, and let it be. You may not raise a gazillion, but you should raise some. Be aware that many aquatic insects will eat fry...especially back swimmers.