try frozen mussell cubes, frozen squid cubes, mysis shrimp cubes, krill on occasions. clams, mussells and shrimp from a grocery store. those are all things mine have available to eat and seem to love. the krill they arent too fond of but will eat it when i feed it, but dont give it too often it will cause lockjaw for the puffers. if you have a good sized LFS check out all the frozen foods they have to offer. one close to me has a huge variety of frozen foods and always seem to find something new to try out everytime i go there. ghost shrimp make a nice snack between meals too and its fun to watch the puffers chase them around