Everyone assumes that all chicken owners live near a State LAB and that is not the case. Therefore, NOT KNOWING what the problem, you must treat the symptoms. NO bleach will NOT treat Cocci, but it will kill other pathogens and that is a start. NOT everyone has access to Oxine and by the time you order it online all the chicks will be dead, and with every bite of medicated feed, you are treating (Low dose) for Cocci! SO, vitamins are a GOOD thing here, just in case they are vitamin deficient, and it will NOT hurt them one bit. Not sure why you would ever think otherwise? I am guessing these birds being so young do NOT Live on the ground, and yes, it you have a plastic tub, cleaning it up really well is always a FIRST order of defense in caring for chicks. Just saying.