All common wall algae are green, but the genus Trentepholia produces a red brownish pigment and is often called red algae. Algoclear and a wfp for the green and red algae.
Black marks are more tenacious .This Black aglae/streaks occur mainly around window sills and roof line The culprit is a filamentous fungi finding enough food from (in part) dead algae. It is a second wave contaminant. They excrete a black melamine protecting them from UV light. The fungi dies in less than an hour, but the melamine will take time to decay into a water soluble compound.