Oh are these your Cinco de Mayo Poults? They probably just think that drinking is a really fun, new trick and they're giving themselves watery poo because they're obsessing over it. Try giving them something else to obsess about. They really seem to need to focus on something. I had mine fixate on a piece of styrofoam that I used to make part of their brooder. I had to distract them by putting a suet block in there for them.