Goldfish are omnivores and should be fed a variety of food types. Their diet can include high carbohydrate goldfish flakes, shelled peas, blanched vegetables, daphnia, bloodworms and brine shrimp.
Goldfish should not be overfed, as they are prone to bloat. While goldfish can be fed 2 to 3 times daily, they should only be fed the amount that they will consume completely within a couple of minutes. Leftover food contributes to poor water quality, which causes stress-related illness in goldfish. Any uneaten food should be removed from the tank immediately to prevent it from rotting and causing spikes in ammonia or nitrite.