Goo Gone Grout & Tile Cleaner 28ozGoo Gone Grout Cleaner’s foaming formula works fast to break down the toughest grout stains caused by mold, mildew, soap scum, and hard water. Removing dirt and mildew from grout is one of the toughest tasks in the home. Goo gone grout clean and restore makes cleaning grout quick and easy. The innovative grout cleaning foam clings to the surface and penetrates the toughest dirt, mildew stains.