A couple of weeks ago I used a white LC pad to apply FPII. After finishing I rinsed the pad thoroughly and believed I got all the product out, then let it air dry. Once dry, I placed it into a ziplock pad. When I looked at it tonight, it had all kinds of dark spots which looks like mold. Is this possible. Is my pad now ruined? Guess I should invest in a brush to scrub the pad after rinsing. Any thoughts? Thanks