Introducing new chickens to the flock

[Bernsen92]

So for some context, I'm right at 1 year of keeping my own chickens, and i'm sitting at 6 Black Australorp hens, 1 Egyptian Fayoumi hen, and 3 Dark Brahma roosters. yes that's too many roosters, but since one of them is very social, I plan on culling the other two this weekend. one of my BA's went broody and hatched out some Australorp Brahma crosses (will be making a post just about them), but since only 2 of 7 eggs hatched, I rushed down to Tractor Supply and bought 5 each golden comet and ISA Brown pullets and thankfully the mama instantly took them in, but abandoned all of them 2 weeks later to rejoin the flock.

So right now the chicks just hit 6 weeks old and I was planning on letting them out into my free range flock at 8-9 weeks. what should I be expecting? will the rooster attack or try and breed the young pullets? will the older hens attack them? the brooding coop is 10x10 indoors, and I have the option to put up a temporary chicken wire fence that would give them another 10x10 outdoor, and maybe do that for a week maybe?

I know that was long winded but any advice is welcome.

 

[Dottie the Chicken]

I would recommend waiting until the chicks are the size or almost the size of the grown birds. Make sure that when you do put them together the young pullets have a place to escape from getting picked on.