I am new to chickens and have learned a ton from you folks at BYC. Here is my problem: I purchased 8 chicks from our local feed store 11 days ago: 2 BR, 2 Light Brahma, 1 GLW, 1 Maran, and 2 EE. All but the EE's were 1 week old when I acquired them and the EEs were 2 days old. All was well until day 5 when one of the EE's started aggressively pecking the others. Thinking they needed more space, we expanded the brooder and it is now 3' X 5.5' Things seemed fine until two days later when we noticed several chicks with bloody wounds. Sure enough, it was our EE Frida (who we now refer to as Frida Kruger). I treated the victims with blue wound care spray and separated the perpetrator in the brooder using a wire fence so she can see her "friends". It has been 2 days of solitary confinement. I have observed her continuing to try to peck through the hardware cloth if an innocent chick happens to lie near the fence. Do you kind folks have any suggestions for me? Do mean chicks typically grow in to mean hens? At what point do I try to reintroduce her to the flock? At what point do I give up and return her to the feed barn (If they would even take her back)? BTW the temp in the brooder seems fine based upon the chicks behavior and I added a rock for them to jump on and a small perch so I don't think it is due to boredom. Any advice is GREATLY appreciated!