Should I switch everybody to Chick feed in the coop?
Or should I build a separate wall to keep the chick's away from the main group ?
Any advice would be great thanks!
Firstly, yep, mamma will protect the chicks from the other hens. Depending on how you keep your chickens (I free range mine), in my experience, adults ignore chicks until they are about 4 weeks old and then some chicken manners are exercised.
Having said that, the issue of feed is something to consider. I built a portable mini-coop that sits in the main the coop with water and chick feed in it. Momma and chicks sleep in the mini-coop, but i put the mini coop outside during the day time and let mum do her thing with the chicks (after 2-3 days) - she takes them back to the mini coop to eat and drink and the rest of the time the chicks are taught by mum what to do and what to eat, where to dust bathe etc. If the rest of your flock is fed growers food, then there should be no issue.
Other members do things differently, I'm sure and it will be helpful for others to share their experience. Very few things are caste in stone when it comes to chicken husbandry, so read through other posts and search for "hatching chicks with a broody hen" (or something like that) and you will see lots of sources that should give you an idea of the range of approaches used. After that, you can see what may fit your situation best.