Wow, those are crazy price differences. I've been using sweet pdz in my poop tray, but honestly, I'm not sure I'm going to get more when this is gone. I throw the scoopings into my compost pile, but the PDZ doesn't seem to really break down. I have deep litter in my run, so when I used pine shavings, those just got tossed into the run. The pdz does save time for me, though. Maybe I'll feel differently when the 3 new girls join the other two, however. Seems weird that you can't get the same grit though. You could try throwing a few shovelfuls of dirt into the run once a month for them to pick out small rocks. My doves get a sandlike grit, though, and their seed mix is as big as anything in chicken scratch, so it must be doing the trick. If you are only feeding chicken feed, they don't really need grit for that.