Here is a feeding schedule that I try to follow.
less than 50 degrees
Do not feed Koi
50 - 55 degrees
4-5 times per week if Koi are hungry
Fish Food labeled Spring or Spring & Fall it's high carbohydrate and low protein. It's Wheat germ based food, Cheerios as a treat.
60 - 65
Once or twice per day everyday
Fish Food labeled Spring or Spring & Fall it's high carbohydrate and low protein. Vary diet with vegetables or fruits.
65 - 72
Once or twice per day everyday
Now you can choose fish food for purpose labeled either Growth, Color or Staple. These are higher in protein. Vary diet with vegetables or fruits.
72 - 80
3-4 times a day everyday
Feed fish food for purpose labeled either Growth, Color or Staple. These are higher in protein. Vary diet with vegetables or fruits.
Hope that helps