I tried the cups (with the yellow pecker thing) and my hens kept them filled with debris. I tried the hanging nipples and they leaked. So, my latest is a large kitty litter container with the horizontal nipples. I still have a couple of them leak, but out of everything I have tried it seems to work the best. I would really like to have a container on the outside of the run for space purposes. Just thinking of things since I am redoing.