Composite Deck Restorer contains a color indicator that turns yellow when you mix it with equal parts fresh household bleach. If the Restorer/bleach mixture doesn't turn yellow within a few minutes, the cleaning properties of the bleach have expired. For best cleaning results, PSC recommends disposing of the old mixture. It's safe to flush down the toilet. Mix a new solution with new Composite Deck Restorer, and fresh bleach. Be sure to check the expiration date on the bleach container. Before adding the bleach to the Restorer, test it. Mix a teaspoon of bleach with a teaspoon of Restorer in a glass jar. Use a plastic spoon. If the test mixture turns yellow, you've got good bleach.

There are two reasons Composite Deck Protector might not bead water. One is that it hasn't finished curing. Though Protector dries enough for light foot traffic within 24 hours, it may need up to 72 hours to develop its maximum water repellency. If it's still not beading after 72 hours, it could be that some residue from the cleaning process remains on the deck. That won't hurt anything. Just give the treatment another day or two to cure. If it still doesn't bead, try re-treating the deck. Re-treat a small test area first, and let that cure for 72 hours, then check for beading.

AfterKlean isn't made to produce a beading effect as pronounced as Composite Deck PROTECTOR, but you should still see some beading. If you don't, it's probably a matter of letting the treatment cure a little longer. If there are still no beads after another day or two, try re-treating. Always do a small test panel first, and let the test cure 72 hours.

Dirt and debris on your deck can get wet and support growth of light mold and mildew, even after treatment with Composite Deck Protector. It's easily cleaned away, though, because Protector doesn't let mold and mildew root itself into your deck. It won't let the dirt penetrate either. A quick cleaning with General Purpose Outdoor Maintenance Cleaner gets rid of soiling and any growth it may have allowed. Monthly, quarterly or semi-annual cleaning--depending on how heavily your deck is used--will prevent reoccurrence. If heavy mold and mildew appears, use PSC Composite Deck Restorer mixed with fresh household bleach.

Composite Deck Restorer is safe for use around most landscaping and building surfaces. However, the bleach you add to Composite Deck Restorer can cause problems if spilled. Bleach can kill plants and discolor surfaces. When using bleach, always wear safety goggles and rubber gloves. During cleaning, be careful not to get the mixed cleaning solution on anything but the deck. If possible, wet down nearby surfaces before you start cleaning. Run sprinklers on nearby grass and gardens during cleaning. With these precautions, a little cleaning solution splashed on house or landscaping won't hurt anything. If you spill the bleach or mixed cleaning solution, hose down the affected area right away. If you catch it quickly, you should see little to no harm from the spill.

If a stain has been on your deck for a long time--years, for instance--it may have penetrated too deeply into the deck for the cleaner to reach. Many stains like this can still be removed by making a “cleaning poultice.” Here's how:

Combine a clay-based cat litter with PSC General Purpose Outdoor Maintenance Cleaner. Make a paste with a consistency similar to toothpaste. Trowel a 1/4-inch thick layer directly on the dry stained surface. Cover the paste with plastic wrap and tape the edges to the deck. That keeps the poultice from drying out too fast. Leave the poultice on the deck overnight. As it slowly dries, the poultice will draw the contaminants out of the deck and into itself.

After 24 hours, remove the tape and plastic wrap. Let the paste dry completely. Then trowel it up. Hose the area down with fresh water, and let the deck dry. If you still have a stain, call PSC toll-free at 1-800-354-2926 for recommendations.