I have a lionfish that will only take feeders. If you are going to feed feeders, it is best to stay away from goldfish because they are very high in fat and bad for the liver of the saltwater fish. Ghost shrimp that are gutpacked with a nutritious marine diet are best but they are too clear and small for my lionfish to see, so he survives on platies. It is the best I can do for him. Sometimes you have no choice. I continue to try to convert him to frozen. Occasionally, he will grab a piece of frozen shrimp, but not enough to survive on.