I was wondering if I could get some suggestions for a two week old silkie chick that isn't thriving? They are all fed a 20% protein starter crumble in which I mix some diatomaceous earth and water with some Bragg's apple cider vinegar in it. This chick is now about half the size of the others, and is still pasting up regularly. No problems with any of the others. They also get handfuls of fresh greens occasionally. Thank you!