Whoo hoo! We had 6 8-week old, sex link layers a few weeks ago. Two weeks ago we bought an 8'x12' coop that came with 10 heritage breed chickens and my parents gave us 10 more sex link chickens (one was a roo) that a neighbour was getting rid of (they're only a year old. His son moved out and he didn't want the work!). Anyhow that's 3 flocks we had to get together before the cold weather hit. I didn't know about quarantining (we lost one sex link hen, maybe because of that? I know for next time) so we tried them together right off. Ouch. The little Cochin bantam roo went after the huge sex link rooster and my little laying chicks (the Princesses) got picked on something fierce. So we kept temporary coops up and free ranged them all together. The sex link roo and his hens LOVE this. They'd never been out of their pen before. Within a couple of days I was able to move the princesses into the coop. Last night, with a weather warning of snow and a drop in temperature I decided to chance it and move ALL the chickens into the coop. Success! No fighting! Darth (the cochin) and Captain (sex link roo) stayed on opposite sides of the coop on their respective roosts and kept out of trouble. This morning the dynamics have slightly shifted and the two flocks seem a little more comfortable with each other. Phew! Just in time too as the temporary coop (a small dog run wrapped in tarp) was getting damp and gross anyway and it's definitely starting to feel like winter is sneaking up on us. Anyhow, that's 2 weeks to get three flocks comfortable with each other. It probably helped that two of my four roos are not dominant and that we have a good number of hens.