Goldfish are diurnal creatures and are most biologically inclined to forage for food during the daylight hours. Morning feeding is vital to provide them with the energy and nutrition needed for the active period after waking.
During the warmer spring and summer months, goldfish may also benefit from an additional meal in the mid-afternoon, but during the colder fall and winter months, when their metabolism slows, they should only be fed sparingly or even fasted for a few days to avoid overeating and potential digestive problems.