I have 8 chicks and they have been on medicated feed since I got them and I even put them on an antibotic in their drinking water for 6 days when I first got them. Now one of my chicks has diarreha. It a watery brown color. I don't see any blood in it. They are all acting normal and eating and drinking good. What can I do to stop the diarreha? And what could it be?