Spilled drinks, barbecue mishaps, kids’ popsicles; a lot can happen to a deck in the summer. One problem with composite decks is their tendency to stain. Even a heavy rain can leave water stains. While you can clean a composite deck, it requires specialized chemicals that can strip thin layers of finish off the boards. This shortens the deck’s lifespan and makes it more susceptible to mold and further staining issues.