We now use the cups. Tried the nipples but the girls just didn't seem to like them for some reason. They seem to like the cups. The picture below shows how we did our watering system. With cooler weather coming up I will be watching to see if the water in the cups freezes or not. The water supply line is hooked into a 5-gallon bucket located outside of the run. Since I live in the SouthEast USA, and we don't get extremely cold weather here, I'll be keeping an eye on things and problem-solving as any issues come up.