For keeping your shower curtain free of mold and mildew try using BLEACH.
Mildew loves shower curtains. Shower curtains usually come in two parts: the outer, decorative curtain and the water-repellent liner. Keeping the liner clean and dry is key to avoiding mold growth. Generally speaking, vinyl, and synthetic liners can be washed in the washing machine with laundry detergent and disinfecting bleach.
Most people throw their moldy plastic shower curtains away, but know that they can be saved and reused. For more cleaning tips and cleaning advise, seek the professional cleaners at Markatos Services Inc.