Oh, Lord, yes, I had my fourth pneumonia in April (both lungs) and I have never felt so sick in my entire life! I was so weak I couldn't stand up without my head going round and round! I had to do the birds a few minutes at a time and go sit on the toilet seat when I couldn't stand up any longer (the bathroom is next to the birdroom) as well as stopping and sitting down on the stairs on my way up THREE times for a mere 16 steps!
The box I mentioned is not only for the treat but also for him to hide inside. My male adores spending some time in them and is always bothering the hens that have laid eggs in theirs (I put out a number of boxes during breeding season). Right this morning he was sticking his head in the quaker's box (there are no eggs in it, the quaker uses nests all year round) and I could hear her scolding him from it which prompted her mate (a male jenday) to fly from my shoulder (he is very affectionate with me) so he could 'scare' him off -LOL
Yes, it will be hard at the beginning but the only way to cure his aggression is to keep him at a solar schedule, reduce protein and let him out for hours and hours so you will have to be very careful, very creative, very observant and, sometimes, just bite the bullet. Try target training and more one on one at the beginning until he calms down some.





