Puddles

So, we have a fish from Katie's wedding that we named puddles (rhymes with cuddles). It was day 2 that Puddles hadn't been fed and we hung out at Zack's parents house. Well, we made a quick trip to Wal-Mart and found some fish food for Puddles. I kept thinking he's going to starve..poor thing. We got tons of food for him and he hasn't eaten anything. Anyone have any advice?