The Java Sparrows diet begins with a basic parakeet seed mix. You can use a standard finch mix, but these often contain a number of smaller millets that the Javas will ignore until the last large white millet is gone. You can also offer them just plain Prosso and any other seeds in a separate dish. Javas will often seek out the oats in a Parakeet mix and will sift through the seed until they find it all. In a gravity feeder, this means they will drain the entire supply and scatter the seed looking for the oats. It is best to offer them and they will eagerly take egg food,green food (Paddy Rice in a sprouted form), live food (ant larvae).Calcium can be provided in the form of crushed oyster shells or cuttlebone.