This past Sunday, I noticed Disney was spending a lot of time at his water dish. After watching him for a few minutes, it looked like he was trying to take a bath. His feathers were all fluffed up and he was dunking his neck and chest in the water - not getting very wet since the bowl is only about 5 inches in diameter.
I put some water in a large shallow bowl and put it in the bottom of his cage to see if he would continue his bath in that. All he did was stare at it. I took it out after he spilled pellets and other food in it.
I'll try the large bowl again soon!