[K_N_L]

The stains seem extreme for a such a new camper. However I have been curious why my roof gets dark stains right at every 4 foot plywood sheet joint. Looking down the camper every 4 foot is basically a black line (note my buddys Grand Design did the same) across the width. Using Dicor cleaner and a bit of Simple green removes most of it but have to suspect something from underneath is at play.