Adding new chickens?

[Spitman]

If i keep them separated within there run , during the day. Can they roost together at night or do I need another coop, until meet and greet time is up?. I have 16 week old's and I'm adding 6 week olds 2 pullets and 1 roo Welly's

 

[Mother of All]

all new birds need to be kept separate for about 30 day and your new one need to be separate until they are about the same size