I use the 8x10 plastic inbox type paper trays from the school section in target. I put like half to a full inch of water and let them splash around, after a few mins you can usually break off the balls.
I had bad poop toe issues with homestead harvest brand food, so I know from experience food can be a factor. My advice would be to put them on just gamebird feed and see how it goes. If the poop toe stops, add one of your add ons and give it a week or 2 to see if anything changes, and do that...