A healthy diet will include all the necessary vitamins.

If your bird is on a nutritionally balanced diet, it should not need a supplement (the exceptions being the breeding pair or the bird starting the heavy molt). Nevertheless, they are commonly given. The best way to give these is in the soft food. Treating the water can be quite frustrating, since many vitamins deteriorate in water. Plus, the birds may simply refuse to drink it. Birds on pelleted diets should not be given supplements.