Usually just the same as the adults, flakes, sinking shrimp pellets, algea pellets and some vege. They'll keep themselves pretty busy munching stuff all over the tank as well.
UPDATE--- THESE FIVE OR SIX I SAW HAS TURNED INTO AROUND 30 ODD SO HAPPY TURNED LIGHTS OF AT EIGHT SORETED MY DOG OUT WATCHED TV CAME OUT LOOKED AT TANK ALL MY GLASS COVERED WITH THEM SOOOOO HAPAAAAAAAAAPY YEEEEEAAAAA
Keep an eye on your water stats with so many extra little backsides the waste is going to sky rocket! Probably do more water changes, but be careful using a syphon without a net on the end because the little blighters are quick to disappear up any tubes. Glad you got so many bubs on your first attempt, as you get a chance inspect them as best you can and you'll probably find for one batch of eggs you'll have quite a few variations in their markings. Love baby BN's they are really cute