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Beyond being unsightly, mold in your bathroom can contribute to health problems. Fortunately, getting rid of mold is not difficult. Add 1/2 cup (118 ml) of white vinegar to your toilet bowl or spray it directly onto mold. Then, scrub mold away with a toilet brush. Another tried-and-true product for removing mold is ordinary bleach. Add 1/4 cup (59 ml) of bleach to your toilet bowl, or spray diluted bleach directly onto mold. Then scrub mold away using a toilet brush. A less commonly-used, but still very effective product for removing mold is tea tree essential oil. Add 10 drops of tea tree essential oil to your toilet bowl or spray a tea tree oil solution (5-10 drops of oil to a bottle of water) directly onto any moldy spots. Scrub with a toilet brush. If left to sit for too long in your toilet, all 3 of these products could potentially damage the inner-workings. As such, it is important to flush these products out of your toilet system. After scrubbing with any of these products, be sure to flush the toilet at least 3 times.

Summary:
Use white vinegar. Apply bleach. Try tea tree oil. Flush your toilet at least 3 times.