My DH made a homemade waterer using a large metal pan and a 5 gallon plastic bucket. He attached it to the pan and cut the holes to let the water drain out. Our problem is....the water never stops flowing out. If we fill it up it just continues to run on out of the pan. ??? I know its probably something simple we are missing but why does ours not work and the store bought ones do?? Any help is appreciated....this is our first homemade waterer.