For my brooder, play pen etc. I use an old well rinsed juice bottle. I ordered the nipples from Amazon and drilled per the instructions a hole in the hard cap. I drilled air holes around the sides near the bottom and hang it with wire. My day old chicks take right to it with no problem and boy is it better than hoping they don't drown, poop or scratch up shavings in to it. The Older gals will even hang upside down from their perch to drink from the longer one I have set up that is fed from a 5 gallon bucket on the outside of the run; which is great because I don't have to haul a hose into their pace and freak them out.
Notice the silver laced to the left too lazy to get down for a drink, she just reached underneath for a sip without loosing her spot.
That's amazing! I'll have to try this with my next pen. Thank you for the tips!