Dissolve limescale buildup with equal parts vinegar and water. Avoid using commercial products that have anti-limescale ingredients since they could leave the enamel looking dull. Instead, remove the chalky buildup by mixing together equal parts of white vinegar and water. Dip a soft cloth into the diluted vinegar and rub it on the limescale until it dissolves. Rinse the area and dry it immediately.
Avoid rubbing the diluted vinegar over other parts of the tub that don’t have limescale since this could damage it. Apply diluted chlorine bleach to stains. For most stains, mix together 1/2 cup (120 ml) of chlorine bleach and 1 gallon (3.8 liters) of water. Dip a cloth in the solution and rub it over the stain. You can also spray the solution directly on the stain. Let the bleach solution sit for 1 to 2 minutes and then rinse it off. Dry the tub once the stain is removed.
Do not apply bleach right after you apply vinegar, as they will form a noxious gas if they mix. When you need to use both vinegar and bleach, make sure you thoroughly rinse away the vinegar before you apply the bleach, and vice versa.
Soak stains with a paste of hydrogen peroxide and cream of tartar. If you have tougher stains that don’t disappear after using the bleach solution, make a gentle cleaning paste. Mix together 1 part hydrogen peroxide with 2 parts cream of tartar. Spread this paste over the stains and let it sit for 30 minutes to 1 hour. Use a soft cloth to wipe away the paste and then rinse the area. Dry it if the stains are gone.
As an alternative, you can use baking soda and vinegar to remove tough stains. Sprinkle the baking soda over the stain, then spray vinegar onto the baking soda. The vinegar and baking soda will react to each other, creating a foam. Let the foam sit for 5-10 minutes, then scrub it away with a clean cloth. If the stains aren’t gone, you can repeat the treatment until they disappear.