Ahh ok from your earlier post I thought the coop was done. You don't need the run finished by the way, they can be moved out with coop only.
Can you get a further back photo of the brooder? You might want to consider getting some very large cardboard boxes like melon or appliance boxes and...
Can't tell how elevated it is from the photo (since we're looking top down) but brick height is usually about right for chicks.
Your feeder is awfully close to the water, which is probably also contributing to the soiling issue. Move them further apart. It also looks like this is all in a...