cwarrior 14 Report post Posted February 18, 2011 Hi, I am looking for a product to remove black streak from the white painted wood of a pergola. Not sure where they came from- could be from the metal rooftop. I've tried gutter grenade which works great on al. gutters, but it doesn't touch these streaks. Anyone recommend a product? Thanks, Mark Share this post Link to post Share on other sites
Paul Kassander 26 Report post Posted February 18, 2011 Could it be an algae growth? Did you try a house wash mix with bleach? Share this post Link to post Share on other sites
carltoncleans 16 Report post Posted May 4, 2011 A painted surface or composite material? Share this post Link to post Share on other sites
