OK, so some of my eight girls have started to show signs of getting ready to lay - noticeably coloring up in the combs and wattles, and on this past Wednesday, turning 18 weeks old. So, on a whim, back on this past Monday, I laid out some crushed oyster shells on the ground - just as something new for them to check out as I plan to have it available for self feed when all are laying. I had read that the consensus was that it wouldn't hurt, and that they seem to know best if they need it or not by self feeding. Well, by Wednesday, the pile that I put out in the run was all gone. So, I put some more out. This morning, I noticed it was gone again - for reference, these piles are probably a couple of good heaping handfuls in size. Tonight, after work, I check on the ladies as I always do, and on the floor in the corner of the coop is my first egg! I don't know if the oyster shells had anything to do with it or not, but I found it interesting. Tonight now, I've been researching the Scratch and Peck feed that I use, and the current Grower that they are on has 1.30% calcium. Their version of Layer has 4.75%, so quite a jump up. I know there are many variables in all of this, but I was just curious if I should finish out the roughly 20 lbs of Grower I have left, or if I should go ahead and make the switch to Layer now that I got an egg? Maybe get a bag of Layer and blend the two together until I run out of the Grower? I'm not really worried about the cost of switching over, and I'm not trying to over think it. I just want what's best for girls. If it makes any difference, 3-4 of the girls haven't started to show signs of coloring up yet, despite all of them being the same age. The flock breakdown is 3 RIR, 3 PBR, and 2 EE.