Birds use up a great deal of energy during the day and the main source of providing it is the seeds which they eat.
If your bird doesn't like anything but seeds, make sure you give him a big variety.
Also, you can give them millet spray and things like that, you can purchase at the local pet store.
Loui loves his millet spray!
Greenfood and Softfood.
The list of green foods that can be safley given to your bird is too expensive to be listed here so it is sufficient to say that most vegetables in the household kitchen can be tried on your birds to see which they enjoy. Same is equaly true for food. Foods to avoid are avocado, rhubarb, chocolate, caffeine (these are all poisonous), and spinach and parsley (these bind to calcium).
Wild plants are also enjoyed by your parakeet, and among the more populars are dandelion, chickweed, groundsel, clover, and any wild grasses. Some plants can be poisones for your birds, so please, make sure you research about it, before trying anything.
Berries, such as blackberries, and rose hips may or may not be eaten by parakeets, if you see wild birds eating them by all means try giving them to your birds. When collecting wild plants, avoid picking them from areas that may have been fouled by motor fumes, dogs or spead by chemicals.
When feeding green foods, always remove any that remains uneaten after a short while as it will quickly sour and be of no benefit to the birds. For this reason it is best supplied in early moring or late afternoon when the sun is not at it's highest.
Parakeets, will also welcome the addition to some soft foods on their diet. Below are some of them:
Bread soaked in milk.
Eggs (both scrumbled and hard boiled).
And indeed any mash that is moist. Most are based aroud milk, egg, or bread but all manner of foods are found in such mixtures and will include mung beans, soy, cereals, and cookies.
CAUTION
Parakeet owners who feed their birds a sensible varied diet really have no need to give numerous additional supplements in form of powders, liquids, and so forth. However to avoid giving these supplements, you must be absolutly sure that your pet is consuming all of its properly balanced diet. Talk to your vet or pet shop representative before dismissing the use of vitamins.