Past few years I used buckets with nipples in the bottom and a bucket heater from local farm supply store. I had the nipples freeze up a few times but not for long. This year I took a piece of 1.5" pvc, drilled nipples into it, put heat tape cord down both sides of the pipe, wrapped in foam insulation, wrapped whole thing in electrical tape (chickens will peck at foam). Hopefully it works! Now it is hooked up to hose with pressure regulator but I also have five gallon bucket (with bulkhead fitting on bottom) connected to pipe as a reservoir. I plan on putting bucket heater in it during freezing temps and disconnect hose. I only have about three months when I can't use garden hose because of temperature.