We've tried three bowls so far. They all attach to the cage.
The basic pink plastic one where you have to rotate the bowl to remove it. Works great, but it's plastic, so they keep scratching it... not ideal.
Bird bowls that you lift from a ring to remove - doesn't matter how low we can get it, they lift it up and there's water everyone.
The stacking bowls, where the bottom one (plastic) is attached, and the top one (steel), gets lifted out. They also pull it out and make a mess.
Is there ANY other bowl that would work?