On the subject of water bowls, in warmer weather fresh water, doesn't stay fresh for so long. And, if parrots are in the habit of throwing their food into their water bowl this will turn the water sour even quicker, and harmful bacteria will begin to take a hold. So, make sure water is kept out of direct sunlight and if food contamination is a real problem, consider moving the water and placing it on top of a heavy terracotta flower pot, so it is away from the food, but off the ground. It is also important that water dishes are not allowed to become slimy, which can also attract disease.
- In Parrots Blog