to get rid of the nasty black gunk in your drain: 1. Boil a pot of water. 2. Meanwhile pour baking soda down the drain. 3. Once the water has reached a rolling boil pour it down the drain. 4. Let the water and baking soda work at decomposing and sterilizing the grime for 10 minutes. 5. After 10 minutes, pour 1 cup of bleach down the drain to completely kill any remaining mildew or bacteria. this process every few months. It will also keep the nasty mildew smell at bay.
Once a month, add a cup of Distilled White Vinegar and a cup of baking soda during the HOT cleaning cycle. pour them directly into the drum. Then, add about ½ cup of vinegar and ½ cup of baking soda into the detergent dispenser.