FYI......
In the aquarium, the feeding of small freshwater live fish, e.g., guppies/mollies/goldfish feeders, should be considered an extra special treat and should not become a steady diet as it lacks some important fatty acids. Therefore lionfish should be trained to accept defrosted or freshly prepared marine shrimp and/or various kinds of marine fish flesh.
Keep in mind that goldfish feeders are not only NOT nutritious, but their cost will soon far out weigh the cost of the feedee. Feeder goldfish also carry many different bacteria, fungi, and protozoa that can cause parasitic and infectious diseases. They can also cause blockage in the digestive track, and/or kidney and liver damage in the feedee, which usually leads to the consumer's death.