I used it the other day for the second time and fell in love with it. The first time I used it, it was on a pretty dirty, well really dirty car and didnt do that great. I want to start putting it in a pesticide sprayer thing and use that before I put the mitt to the car. My question is does it matter how long it stays in the sprayer? would it go bad if I dont use the entire sprayer on one vehicle and a week goes by without using it. Should I just dump it and put some more or will it be okay? I wont use it on every car, just the real dirty ones thats why I ask. I dont ever want to wash a car the "normal" way again. This stuff rocks!