Coop question: can I have water only in the run? That means when the pop door is closed at night they won't have access to any water. I am also thinking about using those auto water cups, does anyone use them? I can't figure out what all you need to get in addition to the cups and brackets. I want to use a five gallon plastic pail with a lid and mount it to the back of the coop with one cup in the coop and then one or two under the coop (coop israised 18" off the gound.) I only have four hens.