I am wondering where the info is coming from also? Not saying anyone is wrong but I can't find anywhere on google that states once you mix Chlorhexidine gluconate with water the chlorhexidine looses it's effectiveness after a certain ammount of time. It's not even on pro exotics site unless they send you a piece of paper in the mail stating that when you buy the pure concentrated stuff from themThey should not even say mix one ounce per gallon if most people are not even going to go through a gallon weekly. They should just give you the ratio for a spray bottle and tell you that it looses it's effectiveness in a week. I know Deb has said it looses it's effectiveness in a week too so maybe she can shed some light on the issue...