how can i clean my rubber seal on 1300 Hoover special edition?

Help!!!!
i have horrid black slime on the rubber seal of my washer!! My washing is getting ruined and whites have to be thrown, had the washer 4 years, the seal and drawer replaced at a cost! Used everything going to try to clean it, calgon, soda salts, bleach, you name it, at my wits end..