This long-forgotten gem of a cleaning agent may be used with a little water or vinegar to lift even the most stubborn stains. Unattractive grout driving you batty? Mold and mildew stains got you reaching for the Prozac? Burner pans and casserole dishes giving you fits? Cream of Tartar is your new best friend.
1/4cup bleach, 3/4cup baking soda, old toothbrush. I put it on the cracks and let sit for an hr took a brush scrubbed it off didn't have to scrub hard just had to get the harded mixture off and rinsed hot water and my tiles and grout super white