No problem using white light.
But then my brooder is actually the liner to a pick up truck. We framed the top and put in chicken wire and closed in the open end. Works great. Is in the garage. 100 W bulbs work great but I have two lights and next week when they turn three weeks will remove one getting ready for the small brooder in the bathroom for the next hatch.
My chicks move away from the light as they don't need as much heat. They sleep fine....all over the brooder. They play for a while, testing their wings because there is room for running and take off....they have no problems eating and they certainly are not pecking. Smashing each other sometimes in flight....but have not seen any pecking.
This is the second group I have used this brooder for and it works nicely for a long time. I have a small boulder in the brooder as well as two pieces of firewood and they roost on that. Also, two flat bottom containers that I fill with play sand....chickie sandboxes and they use them too! Chicks are happy and content. Plus, they have lots of room to roam.
I do have an issue once the new ones hatch because I won't put them together. I am going to frame out a divider to put lenghtwise in the brooder and keep the new ones on the smaller side and the three week olds on the bigger side. I have sold some so there are only 15 now. The next hatch could possibly be 40.....all eggs are showing movement!!! Oh, my!
But as far as the light goes I have not had a problem. But, I think having lots of room and things to play on helps.