I an so sorry to be so negative but with a fancy PVC, horizontal nipple system my coop stunk to high heaven and my flock used about 3 gal a day in the summer. It is now winter and because I messed up the cable entry to the pipe for the heater and it leaked, I removed it and put back my heated, hanging drinker but it failed. It developed a low level electrical leak and chickens wouldn't drink from it. As to the electrical problem, the drinker did not have 3 prong protection so my ground fault system didn't see it. Never buy unprotected drinking equipment. All heaters must be 3 wire and plugged into a ground fault system. Now am using the original heated dog bowl drinker (over 10 years old). Guess what???? No smell, no spill, less than a gallon of water per day and with my new, amazing, exciting fill/clean method it's easy to keep up

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I take the nearly empty bowl out (very light, no spillage) and take it to the bathroom in the barn to clean. Fill a pail with water and carry both back to the coop. Place the empty bowl on it's blocks (very light, no spillage), Fill it with the pail (no splash or spillage), close the door and I'm done. Not what I planned or dreamed but it works and no waste, no spill, no smell. I may be done with the nipple experiment, not sure yet but will say; If I were to do this again, the water system will be in the run, at the outer fence so it can drain into the yard and filled with an underground, heated water line with float system. Climbing ladders with buckets to fill it is no longer on my list

I will never, every attempt to use nipples inside the coop again, ever!
If I had a large flock I might consider nipples again but with the above considerations. Sorry to say but they do leak (mostly from drinking spillage), even the horizontal ones, even brand new ones and the water mixed with the manure is very, very smelly! I have spoken against the open bowl many times but right now it's my best solution and this flock is not quite so messy so it stays clean all day till I refill it. With 19 birds including one turkey, I fill it and clean it once a day. My guess, about 2-3 quarts of water per day. This summer I may have to add another bowl to provide enough water for them but for now, one seems to be enough. To be honest I prefer the hanging drinker but having to fill it from the bottom and no 3 wire heater is a pain. They do stay cleaner but filling every day is too much hassle. (they are heavy, hurt my fingers (I have trigger finger) to carry them and still have to be cleaned and filled every day)