do you have a largish cage you can move all the chicks out to the new coop Put something on top so they dont get pooed on... then keep them there for a few days and open the cage just a little so they can come and go but the big birds cant get in.
Thats what I do for the Guineas....
deb
I have a massive dog crate. I was also thinking it was probably a good time to separate some of my bird so I know who I am breeding, and who's laying what... so it will be a win-win to put the babies in that coop with some of the adults and move some of the adults out to the older coop.