So, after reading through some advice here, I decided to keep continue feeding start/grow to my hens that should be laying any day now. I read that I should simply offer oyster shell (or equivalent) free choice and the non-laying hens will simply not eat it. My problem is, I'm not sure what to put it in. I've tried a small tray, and they just keep turning it over. Any suggestions on how I can give them calcium and grit as a side dish without having to buy another large feeder so they can't turn it over?