Birds eat little at a time but eat often. The feeders must always be full with the basic feed. If one of the feeders is empty at the end of the day, it means that it was not filled sufficiently. All dry food (seeds, pellets) can remain in the feeder for a few days. Therefore, it can be kept in silos or large feeders. Uneaten fresh food (rice, vegetables, fruits, etc.) must be discarded at the end of the day and the feeders must be thoroughly cleaned.
Food must be plentiful and varied. You cannot limit the bird's diet to seeds and water and expect it to be healthy. Just as for humans, it is important to choose from all food groups. Seeds and pellets are important nutrients but nothing can replace fruits, vegetables, bean mix, nuts (unsalted and not roasted), eggs and even well cooked meat from time to time.
The above picture shows some of the foods served to birds on a daily basis.
Fruits and vegetables may be hung on a small metal rod (kebab) thus giving the bird easy access to the food and preventing the pieces from falling to the bottom of the cage.