I found this which may of be use to you :The baby fry feed on small organisms called infusoria and algea. To grow infusoria for feeding just get a jam jar of pond water and run it through some cotton wool or muslin to get out any larger predatorial organsims like daphnia which will eat the infusoria and add hay the water. Leave it for a few days in a dimly lit room at about room temp. and when you next look you should see lots of tiny white dots in the water which, if looked at under a microscope reveal to be lots of types of infusoria in their millions. these can be fed to the fry by adding them to the tank. To get more just add some of the old water containing the infusoria to boiled tapp water with hay and repeat the other proceedours. As the fry grow their diet changes. When they reach about half an inch they can be fed small organisms like daphnia or cyclopses. These can be obtained by dragging a net through water where they can be see or they can be purchased from aquarium dealers. Soon the fish will eat the same food as the adults and will quickly grow.