I just had a similar scenario. I had 3 chicks (2 Wynadottes and 1 Turken) then later decided that I wanted a few more. I added 5 new chicks to the original 3 (then 2 weeks old), 2 Iowa Blues, 2 Welsummers and 1 Golden-Spangled Hamburg. All got along fine after getting pecked on the head a couple of times. No biggie! By the way, I have mine brooding in a 1/2 ton Macro bin.