am i going about the introduction right

i have 4 ee,and a rir roo that are about 6-7 weeks old.and 3 ,mixed breed chicks that are about 8-9 weeks old,2 i think are roos. i want them to all go outside together.the past two days i have put them in the pen,with treats food and water together.i also put a small tote on its side as a sort of hiding spot if you will.well if i can put all the girls with just one boy they seem fine.the minute the older to roos show up they start chasing the smaller ones all over. noone seems to be getting seriously hurt,but if they can they seperate,one group will stay to a certain side of the tote. my question is this,am i going about this right,will they eventually just get over it and get along. at this age is this to many roos,the ratio is 3 roos and 6 pullets. i was planning on keeping 2 of them since i already have 6 hens and 6 more in a brooder,so that would be 2-12. i dont really have anyway to keep them together,where they can see but not touch,so any ideas or is this what is to be expected?