you can feed your valentini almost any type of frozen seafood (shrimp,squid,scallop,mussel,clam,fish fillet........etc) it is also important to include some greenery in his diet....i recommend dried seaweed(nori)....i think you can get it from any asian market....or you can always get the prepared marine algae from your LFS......smaller and more frequent feedings are better than one large feeding........i try to feed my valentini/benetti/solandri three times a day.....sometimes my schedule does not allow me to do so......this is not absolute feeding schedule...so feel free to adjust it according to your schedule.....having lots of rocks is also a plus since valentini is a reef grazer....there will be a plenty of his natural diet available....which means you don't have to feed your puffer as often as you will without live rocks....also it's more fun to watch them pick at the rocks.....hope this helps