I know that it is important to give goldfish a variety of foods so I have GF Flakes, Spirolina flakes, frozen peas, homemade gel food, and Brine Shrimp as my main food items (occasionally giving things like oranges and strawberries since they seem to like those). Right now, I switch off every day (I only feed once a day, a small pinch bc I have had SBD problems in the past). So a typical week might look like this:
Sunday- fast
Monday- GF flakes
Tuesday-peas
Wednesday-brine
Thursday-Spirolina
Friday-flakes
Saturday-peas
Is this ok? Or should they get flakes daily and then get the other stuff in addition to the flakes?