I have had grit in one of my coops for about 6 months. I still have some left. It has been stored in a plastic container. I decided to put grit in another coop today, and the grit smelled bad. Since it has been so long since I have used grit, I wondered if grit just normally smells bad or is it possible it has gone bad or moldy (although I saw no signs of mold/mildew). Thanks!