Check the medication in the feed to be sure it is safe for ducks. If not, just use a flock raiser.
There is niacin in chick feed, but not sure of the effect of increased niacin on chickens.
Ducks can swim at any time, just have the water a bit warmer when they are itty bitty and get them dried and back under heat to finish drying when they are done so they don't get chilled.
I give them water to swim and dive and they take advantage from that early on, but also give them something to get a break on if needed. Once they are done with the fun play, I take them out. Fun play lasts longer as they get older. I don't give them access to water to swim in on their own until they can get in and out of the kiddie pool on their own.
Introductions. I let everybody know there are new littles - they can hear and see them, but not get to them. As the littles get bigger, they get supervised visits free in the yard and the bigs can view from afar and usually don't interfere. Then I create a pen where the littles have room and the bigs can check out the pen, but not get in. I find introductions, if taken slowly, work reasonably well.
I have 2 new chicks this year. They will soon move to the chicken coop for nights so the adult chicken can start getting used to them, but can't get to them.
When we do barrier free overnights, there will be lots of checking in on them and we might put a camera out there so we can spy from the house.
Edited by TLWR - 3/8/16 at 8:31pm