Help !!!!!!!!!! NEW CHICKEN INTRODUCED!

i'm no expert but i would figure out a way to seperate them in same coop for a week where they can see each other and then let her out with two different feeding spots maybe idk

Are they actually hurting each other - causing blood? They may just be figuring out the new pecking order. Perhaps the new hen has a dominant personality and is trying to put the other two in their places below her. If they're all about the same size/age, don't assume that the girls who were there first will end up the ones on top.

If there's no blood/injury, I'd let it go and see if it works itself out. Chicken pecking order can look cruel to us humans but it works for them and a well-established hierarchical order is vital to a smooth operating flock. Just make sure you have enough room for all of them so if one wants to escape for a while, she can.

Thanks for posting this! I just got 2 more hens, a RIR and a mutt, and I am worried about my silkie girls! I'll be watching this thread!

Unless they are physically hurting one another to a serious degree, let them work it out.  It is normal chicken behavior that occurs every time the pecking order is disrupted.  Chicken society can be quite brutal.

I always introduce new members to the flock using what I call 'the playpen method," which is described in my blog here: http://eggcartonlabels.blogspot.com/2011/06/integrating-new-flock-members-playpen.html

In the future, it's a good idea to add more than one new chicken to an existing flock at a time so as to minimize the amount of attention the new girl is going to receive from the others AND to give her a partner to pal around with given that the others are already bonded. I hope this helps. :)

we used to fill up a five gallon bucket with water  when the hens start fighting dunk them in the bucket of water it cools them off they usually calm down after that

You should keep the injured newbie separated until she has healed fully. When she is well you can introduce her with the method I outlined here: http://eggcartonlabels.blogspot.com/2011/06/integrating-new-flock-members-playpen.html