The black streaks are a result of electrostatic bonding of tar asphalt from roofing material and other debris to aluminum metal material.
Black streaks on rain gutters.
Rain carries them down the sides of the gutters where they stain the aluminum.
Gutters made 15 years ago are much higher quality than the ones made today.
All gutters are painted metal and over time water run off will start taking away the top layer of paint where the streaks are.
It is a combination of dirt from your roof being washed off and asphalt from your roofing as it breaks down over time decomposing organic.
When it rains the water will drip down the front of the gutters collecting air pollutants debris and other contaminants.
These streaks are caused by oxidation of the pollutants that settle on the top of the gutters.
Streak getter will break down this bond which will allow you to remove the unwanted streaks off your aluminum gutter with little effort no scrubbing.
The black streaks on your gutters are caused when dirty water runs off of your gutters.
These black streaks are a result of tar asphalt and other roofing material s bonding to the gutters.
The black streaks are caused by the runoff from your roof.
You can try a variety of products but success depends on your geographic area.
Black streaks are often found on gutters and fascias just underneath the gutters.