Hi folks, hope your holidays will be wonderfull! The last few nights when I have been "cleaning" my coop down on at floore level I have been smelling something sour in the back of the coop. I have pine shavings about 3 inches deep and I pick out the poo every night then stir the shavings and add a little fresh shavings. This is not an amonia smell . It smells sour. What am I dooing wrong? Am I not cleaning enough? It smells fine after I "clean" up but the next night it stinks again. I usually replace all bedding every two weeks at least. Should I replace it more frequently?