I ordered baby grit from the feed store and it got back ordered. So now I have 3 day old baby chicks that need baby grit asap! All the feed stores around here told me that I couldn't get baby grit for at least a week since no one is carrying it this time of year. I have oyster shells, sand, and red grit on hand right now. Is there anything else I can give them as a substitute for a week?