With regards to the breeding of whites i would like to add that if you leave whites in sunlight some may become creamy or brassy so before fanciers get rid of them be aware of this:

If you have a good cream or brassy bird mate them to a good black one - all the F1 will be black but carry recessive white, these F1 mated together will produce some white chicks these will be good clean whites.the other option is to mate the F1 to a good white and you will again have some - nice whites.the whites from these matings will stay white when exposed to sunlight.