I was given a coop, a dog lot run and a couple of bags of Pavestone Paver Base to use in the run on top of the earth floor. I'm not so sure about the paver base. There's a lot of sand (of course) and it comes with a handy "contains silica" warning. Also there are rock chips (of course.) I was told it would suffice and be useful as dry bath, grit, etc... Anyone use it in their run?