We have rabbits and I am learning to hate rabbit water bottles. I haven't found a brand yet that is easy to fill, easy to clean, and consistently doesn't leak. The metal ball and metal spout tend to expand and contract at different rates depending on the conditions. You have to pick your poison. With our rabbits in hanging cages with wire bottoms, I go for the leaky ones because I need easy to fill and easy to clean and the buns won't get wet with the water dripping below their cages. In a coop, though, wet bedding can be very bad and I won't put my chickens on wire. I saw "chicken nipples" somewhere and am considering giving those a try if I can find them again, but I worry it will give the same results.