Sometimes all it takes to make your roof look spectacular is a simple cleaning.
In most cases, the stains and streaks are a form of algae commonly known as Gloeocapsa Magma. This type of algae thrives in humid and warm climates and usually appears first on the North slope of the roof where shade is.
Shingle manufacturers recommend cleaning your roof when it is visibly stained. Cleaning your roof will prevent the further deterioration making your roof last longer
Plus your roof looks good, making your house more attractive.