I just moved into a 23 year old home in Ft Myers FL. and the patio has chattahoochee flooring which is nice. I have to clean it because it seems to be a little stained here and there (Plus the contractor got some paint/joint compound on it). What should I wash (scrub) it with? Also, I heard something about a sealer? Is that necessary? Please give me step by step instructions to take care of this please. Someone posted a similar question but don't see any responses. Thanks.