OK, I went to the feed store to get the girls another bag (they're first bag of layer food AAAWWW), and figured I should go ahead and get grit too and oyster shell for once that blessed first egg finally comes. The lady says to me, "The oyster shell IS grit". I say, you don't sell other grit, and she says no. So, is oyster shell sufficient or do they need other grit too? I have enough starter feed to last probably most of this week, at which time they will be almost 20 weeks old, so will it be ok to put out the oyster shell even if no eggs have come at that point ( ) ? I do still have about half a box of parakeet grit which I will continue to sprinkle in with their feed until its gone. What do y'all think?