TravertineThe biggest issue people have with cleaning and maintaining a travertine shower is soap scum. Soap scum can damage tiles and ruin the look of a travertine shower. Also, hard water deposits can also start to accumulate in a travertine shower. "A travertine-tiled shower is a constantly wet surface, so upon installation, I strongly urge people to apply the best sealer that money can buy to protect their travertine shower," says Lichlyter. For tough stains: Lichlyter recommends zero-pH cleaners, which are readily available in home improvement stores. Stay away from: "Commercial cleaners that smell good but have petroleum in the ingredients," says Lichlyter. "Petroleum sits on tile grout and causes residue and a dirty-looking appearance." Also avoid acidic substances like vinegar as well as abrasive cleaners and dish soap containing citrus oil.