i am going to make an outdoor run for my standards (3). chicken math says that i need approx 10 square feet of outdoor run space to keep everyone from going nuts. i plan on making the run about 5' x 12', maybe gonna add two more hens. i was reading gail damerows book and she says that you should avoid keeping your outdoor run in the same place, year after year. i cannot move my run around, where i build it is where it stays. my concern was a build up of diseases and pathogens. i will still let them out to free range, just for a limited amount of time. how do i keep a run relatively clean, aside from raking. should i turn over the soil weekly? mix in dg? add wood chips? is disease build up w/ 3 to 5 chickens a reality?