I have a Tendura composite decking covered porch, which was installed approximately 20 years ago, and is no longer manufactured. It's located in Virginia. Corte Clean is the only product that gets the mold stains out. I use to use chlorine bleach. It took two seasons of cleanings to get the impeded stains out the chlorine bleach caused. Additionally, don't use Soft Scrub, as it took several years to get the white out that this product caused. I've been using Corte Clean now for years. I use to buy it locally, but they stopped carrying it, so I now order online.