This is a system you can make that has everything you asked for. This is a gravity system the brass float valve connects directly to the water source. If you don't have a water source just don't use the valve but increase the size of the pail. Look in the sprinkler department of Lowe's or ?. You need a 1/2" thread to tubing fitting in the bucket and on the nipple run. The tubing will be in that dept. too. On the pail you need a nut and rubber washer to sandwich the fitting to the pail. A 1/2" romex connector nut can be found in the electrical dept. washers in hardware. Several of my customers have built this with the horizontal poultry watering nipples and they are all pleased with the results.Has anyone made one with a pvc pipe so you could place several chicken nipples along a distance of it? I'd like to use a 5 gal bucket to supply the water to the pvc pipe because I don't have a water source on that side of the house, and don't wanna mess with a regulator to decrease the pressure to 1 psi to use a garden hose. I am wondering if anyone has made one already that has tips on how I can make one. What did you use between the bucket and pipe and how did you keep it from leaking, etc. Thanks.
Hope this helps.