Bleach is corrosive. I take an empty spray bottle and fill it with a 50/50 mix of distilled white vinegar and water. This makes a great all-purpose cleaning solution that can be used around the house. The vinegar will kill mold and bacteria. The vinegar smell goes away as soon as it dries. Works great, is environmentally friendly, and inexpensive. I usually add just a small amount of dish soap too, but you don't want to do this to clean your cover. The dish soap will get in your water and cause foam.