Cover the area surrounding your masonry with a plastic tarp. Make sure you cover any patio furniture in the area, as well as the surrounding concrete, plants and landscaping features.
Put on rubber gloves and plastic glasses to protect your hands and your eyes from burning because of the cleaning chemicals required to remove calcium stains from masonry.
Pour water onto your masonry. You can squirt it on with a water hose or pour it out of a bucket.
Mix an acid-based brick cleaner, available for purchase from your local masonry dealer, with water according to the instructions on the label.
Brush the masonry with a stiff bristled nylon brush.
Rinse the area with water and the stains should be gone.