Though it may not be as good for them, Phyllis and I have used catfish
food for more than a decade. I gather it is growth oriented. Our koi
and goldies seem to be thriving on it (and the bluegills in our acre
pond). It is so cheap at $12/50 pound bag that we cannot see feeding
other food to our $3.95 koi.

Others will have more formal advice for you.

Jim