I've got 2 one quart plastic waterers that the chickens have had since they were 2 days old. I put them in thier run and they drink out of them with no problem. I wanted to put more water in there so I cut down a milk jug and filled it up and put it in the run. They don't even touch it. How do I get them to drink out of something they aren't used to? I screwed up when I made the run, and didn't make a door, so it isn't very easy to change the waterers.