I don't feed my goldies commercial foods. my 9" black moor had some bouyancy issues with flake food and with algae wafers.
In the morning, they get my current batch of color enhancing
gel food. Here's another
gel food, recipe, I've worked up that will probably be the next gel they get. In the evening, they get shrimp or krill and green beans, peas and lima beans.
I usually keep a slice of squash (zuchini or yellow) in the tank on a veggie clip. I also give them duckweed, azolla and frogbit plants once a day along with some live daphnia. They also get live redworms from time to time. I've also added some of my larger ramshorn snails (which they don't seem to be eating...yea!), but even tho I've seem multiple globs of eggs on the side of the tank, I never see any baby rams. Hopefully, that's providing a renewable food source for the goldies.
I'm seeing nice growth and happy fish so far, tho I have to wrestle with keeping nitrAtes down. The little ones I got back in March are around 7 inches long now and the little chocolate oranda I got back in June is about 5 inches long now.