If you have waterpik mold, there are a few things you can do to clean it. First, remove any visible mold with a brush. Second, pour 1 cup of white vinegar into the waterpik and turn it on to medium-high. Third, add 1 cup of warm water and turn the waterpik off. Fourth, use a scrub brush to scrub the mold off of the nozzle and body of the waterpik. Fifth, rinse the nozzle and body of the waterpik with cold water. Finally, dry them off with a towel. ..