If you have mold growing around your bathtub, try cleaning the area with vinegar and a scrub brush. After you have scrubbed the area, rinse with clean water. If the mold is still there or comes back quickly, lay a few cloths soaked in a mixture of 50% water and 50% bleach for around 12 hours. Rinse well with water after the bleach treatment. Never mix bleach with any other chemicals.