Wet Forget is an outdoor cleaner that eliminates black and green stains caused by moss mold mildew and algae without any scrubbing power washing or bleach. Just mix 5 parts water with 1 part Wet Forget in a pump up garden sprayer. Fully saturate a dry surface with Wet Forget on a cool dry day and leave it. Thats it Just wet it and forget it. Wet Forget goes to work with the wind and rain to gently clean the surface over time. Green stains generally clean up within a few weeks a few days with rainfall. Black stains or heavy stubborn stains may take 6-12 months to fully clean up. Be Patient Good Things Take Time Wet Forget properly cleans surfaces so they are likely to stay clean up to 1 year or longer. Repeat application yearly or when new stains appear to maintain a clean surface. Wet Forget contains no bleach and is safe to use on any outdoor surface including any type of deck siding roof walkway patio brick and cement. Gallon Concentrate makes 6-Gallons and covers 750 - 2250 sq. ft. depending upon severity of the stain and porosity of the surface. Wet Forget - the easy way to clean all your outdoor surfaces