Need help asap! Chicks all pecking each other!

[BBQNuggets]

Help! I feel like a total failure of a Chicken Mother!! I woke up today and discovered blood everywhere in the brooder!
I have 20 chicks (Red pullets, a leghorn and a few random bantams) in a nice large brooder (4' x 5') They are almost 3 weeks old, plenty of food, water, and warmth. Woke up today and found that 10 of them have been pecked at to the point of bleeding everywhere! One of the poor girls has a wing that is completely raw. All of them have had their tail feathers almost ripped completely out.
Here's what I've already done, please tell me what else I need to do! I took out the injured chicks and put antibiotic ointment on their wounds, and I isolated them each in a box.
I also drew red and black dots all around the inside of the brooder to give the other chicks something to peck at.

I have so many questions:
1) Can I put all of the injured chicks together, or do I need to keep them separate?
2) Is it likely that only one chick is to blame for the initial pecking and the others are all just joining in when they see blood?? I have been watching them and I can't find one single perpetrator, rather all of them seem to be to blame?
3) WHAT can I do to prevent this from continuing?? HELP!

I have 10 cardboard boxes with chicks in them yelling at me!

 

[chad-o]

Once they see blood they will all join in. My guess is that the injured ones can be put together. Try it and you should see any problems fairly quickly.

 

[PearlGrey]

Do you have them under a red light, or a white one? My chicks started toe picking right away when I brought them home, but I decreased the ambient temp by 5 degrees and changed my white light for a red one and now they've stopped acting like little cannibals.

 

[donrae]

You'll need to spray the injured chicks with something like Blu-Kote. It's a blue/violet antiseptic spray that masks the red color of blood or open skin. Chickens are drawn to the red and will continually peck at it if it's visible. I'd advise to wear gloves, though, when using the spray, unless you want pretty violet fingers for a week

After they're sprayed, you can try putting them back together, or at least all the injured ones together.

Other than that, I'd say they're likely needing more space, or at least barriers to block line of sight. Any chance of putting them in the coop with a heat lamp?

 

[Folly's place]

x2. My chicks go to the chicken house annex at three weeks, as in last week here in Michigan, with a red heat lamp hung near a corner of the coop. Lots of space, heat, food, and water, and green growing plants to start eating. If you have an aggressive instigator, get rid of her! Mary