Dalmation molly fry

Question
   my parents recently got me a 25 gallon fish tank, oh man was i excited!!! in it now i have 13 fish, a mix of barbs, Cory, a baha/bala(?) shark, an algee eater, one black ghost, a male molly, 2 female Mollys,   a batch of 13, 2 day old dalmatian fry. to start out with, my molly had about 30 fry, it was one of the coolest things iv ever seen... but by the next morning over half of them died. Why?
    oh, forgot to mention i had just got two new mollies from Petsmart... i had asked the worker to give me the fattest dalmatian female they had because i wanted fry. i had all of the stuff. a breeding net, plenty of hiding places, powdered food, and all of my balances were right. nitrite   ammonia at 0.0, my PH was right at 6.4 and my nitrate was at 13.5. i had just hooked up the breeding net, (witch is where they are now) and put her in it... after i fed her... and was walking by and saw her having them. i saw every one be born!! :> but that same day i bought her!!! FUNNY!!!!!!!
      my other question is what to feed my new bundles of joy. right now i have them on a diet of powdered fish flakes.   i know when they get older ill have to give them more variety but variety is also important now for good growth. any suggestions would be greatly appreciated!!!
    the first night i got my male molly, i did a lot of research on fry because i thought it was the neatest thing. its my first time and all!! after my female molly had her fry, it was the experience of a life time. i cant wait to keep doing it in the future!!! but my main questions are why did half the fry die after one day, did i do something wrong?  what is a good diet for the fry at such a young age, and another is should i move them to another 2 gallon tank so they will have more swimming room? for the past 13 hours iv been reading questions to find answers. i am new at this so i need some help. what did i do wrong?
    any advice would be taken in fully!!!!
please help!!!!
sincerely, Abby Clark

Answer
Hi Abby:  It is difficult to say why half of the fry died... It could have been an environmental issue or maybe a genetic issue.  This is one of the reasons why they have so many babies...so that some of them survive.  I feed my fry a paste I make out of boiled egg yolk and water... you can order online at ebay some microworm cultures and these are very good for fry. I would move them as soon as you can to the 2 gallon tank... hope this helps... dave