Not sure how big your run is, but I switched from deep litter pine shavings to sunset rock. It is bigger, rounded and more smooth on their feet than pea gravel. It has been a game changer for me. My coop has a built in pool which I do change every day (30 min tops), but I only have to hose down the run now. I do use straw where they lay eggs and change that as needed. My ducks only stay in there at night, so I dont worry about their feet being on rock all day. Rarely do I smell anything and as long as the rock is hosed down, flies are not an issue either. I do use deep litter pine shavings for my chickens. I rarely have to do anything there because they keep it turned for me. I posted pics as reference.