baby platy!! please help!!

Ill presume you want to save him. I'd just throw him in the fish bowl. Use water from you larger established tank. A mini filter whould be nice. But not necassary. You can get him special Fry food, mine also enjoy my cory cat's brine shrimp pellets. Wait until hes 1/2 grown then toss him back in the main tank. Oh and look for more, Theres usually more then 1 fry at a time

I keep mine in a small 1/2 gallon tank and run a small sponge filter until there big enough to put back in to the main tank. You might be able to get away without a filter but, I would suggest 50% water changes every few days, just make sure you are using water out of your orginal tank. As far as feeding goes I just grind up flake food with my fingers as small as I can get. Live barriers have pretty large fry so this works well and is much cheaper. Best of luck and I hope everything goes great for you new fry.
Travis