Situation: I am a new chicken owner and have three chicks currently in a brooder. One of them (an Australorp- 1 1/2 weeks old) has consistently loose/watery droppings. It appears to be just as active as the others and is feeding and growing fine. She is feathering-in more slowly than her mates (a RIR and Barred Rock), but I'm not sure that is a problem. Food/Water: I've been supplementing their water with apple cider vinegar and probiotic powder. I'm feeding them non-medicated, organic chick crumbles. In the last three days, I've been offering them some dried meal worms and greens (lemon balm) and this chick appears to be the least interested in them. Any thoughts on what might be causing this and how I might be able to treat it? Thanks in advance.