Yep, that's basically it. They should be given a lot of different things. Formula A and B are always good, mysis shrimp will work, krill will be good when he gets bigger, nori/seaweed sheets is something they sometimes like to pick at, blood worms are good because they are small, prawn works well. Just make sure to include a variety of meats in their diet. Also, it is a good idea to give them something in a shell, such as a clam (grocery store), every so often to help them grind their teeth down.