I have discovered that at Wal-Mart you can buy this stuff called McCloskeys Deck Wash (or something very close to that) in the paint department. Its ingredients are Sodium Hyperchlorite, Sodium Hydroxide and water (bleach, lye, and water) so it could be easily reproduced if you knew how much of each product to use. It looks to me like it might just be full strength 6% bleach with a little lye in it (i think there is a Clorox available that has that in it, its probably just rebadged Clorox). Anyways spray it full strength on the gutter, as directed for decks, and let it sit a few minutes and the black streaks/oxidization will just wash away. I learned this the other day after trying a mix of bleach and water and a couple other different cleaners. I even used the two cleaners and a brush on a long pole to scrub the gutters and it did not work as well as just spraying on the McCloskeys deck wash.
Anyways this stuff IS $4.50 a gallon and i think it could be made cheaper if you can figure out their mix, and i personally think full strength 6% bleach would do it but i dont know. As long as you rinse everything real well it wont be a problem with anything.
Anyways this stuff IS $4.50 a gallon and i think it could be made cheaper if you can figure out their mix, and i personally think full strength 6% bleach would do it but i dont know. As long as you rinse everything real well it wont be a problem with anything.