Tub and Grout Cleaner from Ultra Chem Labs is an unparalleled deep grout soil remover using Ultra's Electrolytic Cleaning technology. For grout cleaning, and depending on the level of soiling, simply mix at 16 to 32 ounces per gallon of water. For general restroom cleaning, mix at four ounces per gallon of water. Tub and Grout Cleaner removes mineral deposits, hard water stains, outperforms conventional acid cleaners and is certified by UL TerraChoice's EcoLogo Program for its environmentally friendly food-grade acid makeup. Safe enough to be discarded down drains after use without interfering with costly and extensive sewage treatment, Tub and Grout Cleaner is a perfect tool for all your restroom cleaning needs.