I don't know if he'll like banana.........cockatiels aren't usually too fond of fruits. They prefer veggies. Popcorn and Muffin like apple on occasion. Just a note here. *Never* feed a bird fruit pits/seeds, including apple seeds, because they are toxic and can be harmful. In veggies, avacado is a big no-no. My birds don't like fruits much, but they LOVE broccoli, peas, corn, carrots, and other veggies. Also try nuts...........cockatiels love almonds, walnuts, etc. Only give small amounts on occasion, because nuts can be fattening, but they do enjoy limited amounts, and it is good for them too.