Bleach can do the trick against mold ... Once the vinegar has had enough time to soak into the mold, spray the spot with the mixture, and scrub it with a brush or sponge. Rinse it with water ...
Spray distilled vinegar into the bowl ... and dry spaces don't get mold. Follow the instructions on the bleach label to mix a solution of bleach and water. If you don't have label instructions ...