SNOWCAP can be used to remove well water stains from the bathtub, toilet, sink, and shower stall. IMPORTANT, use with CAUTION, RINSING is necessary when used indoors. SNOWCAP can be used to clean well water rust stains from windows. IMPORTANT, windows should be rinsed immediately. SNOWCAP is not a preventative. It is a cleaner that removes well water rust stains. It will not remove lime or calcium build up. SNOWCAP can be used to remove green fungus from sidewalks and driveways, spray the same as you would for well water rust stains. If a heavy build-up has occurred, a second application may be necessary. SNOWCAP can be used AFTER pressure washing. When pressure washing concrete to remove mold, mildew, and oxidation, SNOWCAP can be applied afterward to whiten and brighten concrete. Just spray SNOWCAP on and let it return your walkway or driveway back to its natural look and color. No rinsing required when SNOWCAP is used outside.