I have (15)- 2 year old hens. and (25)- 6 month old hens and (5)- 6 month old ducks. I was Just looking at other chicken sites and they say to keep your ducks away from your hens. I have a lot of land (everyone is free range), and everyone seems to be happy and healthy. Everyone is co existing together. My hens have their own water supply. But, I have a little swimming pool that i got at walmart and sometimes the hens drink the ducks bath water. I change the water twice a day. So do i really have to separate them?