About a week ago my 10" Oscar stopped eating and began to do the gasping thing. His teammates of many years were fine. I put him in the 55g quarantine tank to recovery from his ailment. I am happy to report he is much better now. He also has gotten his appetite back. My issue is, however, is that be insists on spitting out his old food. At least he's trying to eat. He likes Hikari red and green pellets with the occasional krill pellets. I request advice/recommendations as to where to go from here. Should I be patient and give him no other options? Should I try something else? I appreciate your help and time.