11. Remove Moss and Algae
Bleach can be used to clean bleach and algae from bricks, but you must pretest to make sure the bleach will notharm the surface. Mix a solution of 3/4 cup bleach in one gallon of warm water. Pour into a spray bottle. Spray the sloution onto a small test area and wait 20 minutes. Rinse and inspect the area to make sure the surface is unharmed. If you find the surface is ok, spray a larger area, working in 1 to 2 square meter areas. Spray and let sit for 20 min, and rinse the area with a hose and moderate pressure. Move to the next section and repeat.