how to clean omni stone? I have a large omni stone patio in my backyard that is of a multi-color brown different size rectangles. It is about 9 years old and really needs to be cleaned. I have tried using a deck brush with household cleaners, but it still looks dirty. What do you recommend? I do not want to have to have it professionally colored by an Omni Stone dealer. Also there are some green spots from algae and lack of sun. What do you recommend I do to keep it clean? Thanks
