I have a job in ocean city Maryland. It's out side carpet right on the beach. it's blue carpet and has black grim on it I think it's mold and algae on it what chemistry can I use to clean it. I've tried I lot of prespray on it and nothing works but holding the my wand on it with hot water for a long time. About a minute or more then I move it about a inch and hold it for minute again. I think the hot water heats it. But it is taking along time to clean it. I've crb machine carpet rake every thing.