Hi Richard,
Are you feeding him the same food he was eating in his previous home? Is this an adult bird or is this a baby bird you are handfeeding? You should offer him what he is used to, and if he needs to eat a better food, you can make the change gradually. If you are hand feeding this bird a baby formula, you need to make sure it is mixed properly and is the right temperature. Depending on his age, he may be ready to start eating solid food on his own. Sometimes a hand feeding bird can get an infection and his food will not digest properly. In this case, you need to take him to an Avian Veterinarian – a Vet who specializes in treating birds. If you can provide more information on his age and what he is eating, we can be of more help.
Thank you for asking Lafeber,
Brenda