I make my own bulkheads for nipple waterer buckets. Get a male threaded and a female threaded PVC fitting and a large metal washer, an electrical locknut and a rubber o-ring. These were all things I had in the barn so it just made sense to me to use it. Drill a hole in side of bucket high enough off the bottom for the fittings to turn as you tighten them. Put the o-ring and the male fitting on the inside of the bucket with a little silicone. Then the metal washer with some silicone against the outside of the bucket. Then tighten the electrical locknut against the washer and then the female fitting. Tighten it up real good and let the silicone cure. The metal washer will flatten the side of the bucket a little. After it's cured you can glue the rest of your piping system to the female fitting. I've been using this one for 4 years now and just had to redo the silicone this past summer.