I want to have 2 chickens in a 3x3 coop and a 3x4 run. I would leave the coop door open 24/7 so they can access outside as they wish, but is the run even big enough for the permanent residence of two chickens? I don't have enough space to provide them new grass so this is my only option. How should I manage the coop differently because of this (ex. more hay) ?