Bellatrixed,
I noticed you are sort of new to BYC just like I am. Just started with my first flock last April and I am learning as it goes and thanks to reading lots of posts here I have been able to make changes in my coops and runs to make things better for me and my girls. When you get to the point to move your chicks to the coop and if you decide to use sand and PDZ on the floor, I would suggest to get some nesting pads for bedding on your nesting boxes
http://www.eggcartons.com/category-s/1901.htm
I read in a post that they are great and clean. Right now I am using hay on my boxes but the girls drag some out which is not a big deal, it is just that there is always some poop on the floor and then you have to scoop the hay too. I have ordered some pads and they are on their way .
BTW I have been contemplating the idea of using sand in the brooder, I have been a little hesitant until I read your post. I am getting chicks in May so I will definetly use sand and PDZ after they learn what food look like. Thanks for your input