I’m not a review writer but I was so impressed with Corte clean I had to say something. Deck is 13 years old and I probably cleaned it once maybe eight years ago. It was a mess, you name it, black mold/mildew spots, lichen, moss, you name it. Light gray correct deck. As I filled the sprayer the dogs had to go out, when I came back, the sprayer nozzle was spraying a spot (trigger was locked on accidental) about 4ft in diameter for the couple minutes I was gone. The deck looked brand new! I was amazed. I continued to clean the remainder of the deck and highly recommend Corte clean. I ordered another bag to clean another deck. I’m going to follow the recommended cleaning intervals going forward.