I have 24 4 week old ducklings and the thing that's working for me is a shallow circular pan that would go under a big pot with a hose dripping into it. The hose is hooked through the chain link fence and the little creatures can't move it. This only works because I live in central florida and we have nothing but sand sand sand....so it doesn't get muddy or gross. I have two one gallon waterers that I fill a few times a day because I also have 10 chicks and 9 turkeys in the same pen. This set up has been working for the past week. Every afternoon I get home and let them out into another area with a tub for them to play in. The turkeys and chicks go along and hunt for bugs, etc. Still......it's a whole lot of birds!!! They'll be truly happy when they head to GA and free range!