As we're building our chicken tractor, we made a slight change in design and want to create the outdoor portion (the run) in a hoop style. For those of you who have built such a thing... where did you get the metal pipes that were already curved? Or... would PVC piping work better in this situation? The hoop portion of the coop would be 5 feet wide and 3 feet (approx.) high. We would plan to place the hoop portions about 2 - 3 feet apart for the length of the run. There is already a sturdy base that we can use to attach the hoop pieces.