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The running water in your shower loosens surface dirt and softens soap residue on your travertine tiles. For optimal results, tackle shower cleaning after your shower has primed the tiles for you. Travertine, like all limestones, is extremely sensitive to acids. Use a non-acidic stone cleaner, such as Granite Gold Shower Cleaner or MB-3, and spray the travertine thoroughly from the top to the bottom. Let the cleaner sit on the stone for 10 minutes to begin dissolving any soap scum. Given travertine’s acid sensitivity, always avoid applying vinegars or other citrus cleaners. Fill a bucket with warm water, and begin scrubbing the tiles with it. Use a diamond-shaped brush to wash the entire top row of tiles, applying firm pressure to loosen soap scum. Progress to the next highest row, methodically working your way to the bottom row. This way, dirty water will run down on tiles you’ve yet to clean.  Focus particular attention on any surface holes in the travertine when cleaning, as they can collect soap scum. A diamond-shaped brush makes it easy to clean your shower’s innermost corners easily, but any shape is fine. Be sure to choose 0000-grade steel wool, as it is very fine and shouldn’t scratch the tiles. Lightly buff away hard water stains with the steel wool. Turn the shower on and rinse your newly cleaned travertine tiles with warm water. If there are any spots you can’t reach with the showerhead, fill your bucket up with clean water and rinse the tiles clean manually. Use a towel to wipe down your travertine to remove any traces of stone cleaner. It may be helpful to open a window to dry the area more quickly.
Clean your shower after you use it. Spray your wet tiles with a non-acidic soap scum remover. Use warm water to scrub the tiles. Remove hard water stains with fine steel wool. Rinse the shower with warm water. Dry your travertine with a clean towel.