Keeping New Chicks in Coop w/Six Week Olds?

[Chickmate]

I have 22 six week old chicks in a 10 x 14 one room coop. In two days I'm picking up 10 new chicks which I had planned on keeping in a stock tank brooder in the same coop. I put up a temporary wall of 3' high plywood to keep the older chicks away from the babies (I hope!) I will also put chicken wire over the top of the brooder, but I'm hoping the older chicks won't try to fly over the wall. My question is regarding keeping the new chicks in such close quarters with the older chicks. I know you are supposed to quarantine any new birds before allowing them to join the flock, but I don't have anyplace else to put them. Poor planning when building the coop

What are the chances the older chicks that came from TSC could be carrying something, or that the baby chicks could infect the older ones with something? The new chicks will be about a week and a half old and are coming from a small but apparently reputable breeder. Are most chicken diseases airborne or from contact with the feces? Also, would the older chicks try to hurt or kill the babies if they got over the wall? Thanks for any advice!

 

[Chickmate]

Bump for any advice?

 

[Fred's Hens]

Chicks 6 weeks apart is pretty tough. The six week old has such a physical advantage. Plus, they already have their pecking order established pretty well. I'd say you can raise them divided by a good barrier, like netting so they get "used" to each other, but still. The day will come for integration but the little ones just won't ever catch up until they 4-5 months old, so this is going to be awhile. BTW, yes, they'll easily fly over a 3' dividing wall.