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gstrumke1 · Guest

Black Shingle Roof

Roof Cleaning Raleigh NC · Jul 12, 2011

It is the dead algae. It will go away after a good rain.

Jul 12, 2011

What the Big Pink Elephant said. LOL...
+1

Jul 12, 2011

There is another factor that can cause the brown stain, if you used or rinsed with well water. But it probably what Dave stated.

Jul 13, 2011

And 1 more.
You may not have used a strong enough mix to rid the roof of all algae and you can see the partially bleached algae that's left on the black roofing. It could be well water, but that usually takes quite a while to show up. It could be dead algae, but only if there was an excessive amount of algae. My 20 year guess is your mix was too weak. Hit it again and I bet it's gone!

Roof Cleaning Tallahassee · Guest

Look up my "unhappy customer" post. Same thing you are talking about and looking thru polorized glasses looks twice as bad. First good rain and it should the dead alae away.

The Roof Cleaning Institute Of America Training & Certification Forum "Find A Certified Roof Cleaner Directory"

The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"