Dear Pat: The grout between my bathroom tiles is discolored with dark mildew. Some of the tile is glossy and some has a flat, dull surface. What is the easiest and safest way to clean the grout without harming the tile? — Rita M.

Dear Rita: Dark, mildewed grout is common in most bathrooms — or anywhere else grout and moisture meet. It's a nuisance because even though the rest of your bathroom might be clean, discolored grout makes it appear to be dirty. Luckily, mildew does not damage the structural integrity of grout. So when you finally get it cleaned, it will be as good as new.

It helps to understand the source of the mildew so that after it is removed you can prevent its return. Mildew is a living organism that survives on moisture and minute organic particles, such as flakes of skin, soap, oils, etc.

The microscopic spores sent out by mildew can remain dormant for a long time. While it will be difficult to eliminate all the organic particles the spores grow on in your bathroom, you can control the moisture level. One effective way to limit the reoccurrence of mildew is to dry off shower walls and promote the circulation of dry air by leaving shower curtains and/or shower doors open.

To remove mildew, wash down the tile and scrub it with a standard bathroom cleaner. This should remove most of the mildew if it is not too bad. A few bathroom cleaners to consider are: Mist Away by Reckitt, 800-228-4722; Comet by Proctor &Gamble, 800-926-9441; Tilex by Clorox, 800-227-1860; and Original Clean Shower by Church & Dwight, 800-524-1328.

After you have used the cleaners, dry off the tile. Put on rubber gloves and open some windows so you have adequate ventilation. Saturate some paper towels with chlorine bleach and place the towels over the tiles. Bleach will whiten the grout and also kill any mildew spores it contacts to minimize future mildew growth.

Once you are done with the cleaning, you will likely still have a few dark, mildewed grout spots. Use Clorox Beach Pen gel to clean these difficult spots. Use the pointed end and squirt out the bleach gel over the grout. Follow the instructions on the package and it should whiten even the stubborn spots.

The best type of scrub brush to use to clean bathroom tile and grout is one with stiff plastic bristles. The surface of ceramic tile is very hard, so the plastic bristles, even though they may feel stout, should not scratch the tile surface. Avoid abrasive cleaners because the tiny abrasive particles may scratch and dull the glossy tiles.

To remove mildew, wash down the tile and scrub it with a standard bathroom cleaner. This should remove most of the mildew if it is not too bad. A few suitable bathroom cleaners to consider are: Mist Away by Reckitt, 800-228-4722; Comet by Proctor &Gamble, 800-926-9441; Tilex by Clorox, 800-227-1860; and Original Clean Shower by Church & Dwight, 800-524-1328.

After you have used the cleaners, dry off the tile. Put on rubber gloves and open some windows so you have adequate ventilation. Saturate some paper towels with chlorine bleach and place the towels over the tiles. Bleach will whiten the grout and also kill any mildew spores it contacts to minimize future mildew growth.

Once you are done with the cleaning, you will likely still have a few dark mildew spots on the grout. Use Clorox Beach Pen gel to eliminate these difficult spots. Use the pointed end and squirt out the bleach gel over the grout. Follow the instructions on the package and it should whiten even the stubborn spots.

Another common source of stains on bathroom tile and grout is hard water deposits. Usually caused when water dries and leaves behind calcium, hard water deposits can be a bit more difficult to remove than mildew. Once gone, however, it is easier to prevent hard water deposits from returning.

To remove calcium deposits and stains, saturate some paper towels with white or clear vinegar. Place the saturated towels against the tiles and press them down so they contact the entire surface. They should cling and stay in place naturally. It could take a while, but once softened, these stains can be washed away with a scrub brush and water.

Tools and materials required:

— Bucket

— Scrub Brush with stiff plastic bristles

— Paper Towels

— Rags

— White Vinegar

— Bleach

— Bathroom Cleaners

— Clorox Bleach Pen.

Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com. To find out more about Pat Logan and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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