if you buy the frozen foods from petco, just make sure you thaw them with some kind of strainer ( I use a net) in water and then toss the water. There are a lot of phosphates in their frozen foods and you dont want to add to your tank. Petco sells hikari marine and seaweed extreme sinking pellets which will be good. Just make sure you get the smallest size and dont feed more than they will eat. Petco also sells "New life spectrum" pellets , which a lot of people like. (I have not tried them). Keep in mind not all fish will eat various foods. I have a set of clowns and only one will eat the pellets I mentioned. The other refuses anything bu frozen. So I would buy small sizes, until you know what will work. Its best to offer a variety of foods