Getting ready to embark on unknown territory. Next week my six new chicks arrive. I am planning on installing the heating pad cave in the grow-out pen in the run. There is sand covering the natural clay soil. The heating pad cave will be sitting on top of the sand. I'll provide a wooley pad inside the cave for the chicks to sleep on, but should I be concerned with them being on sand during their first week, especially since Alibabba has reported losing a chick to eating sand?