I have a customer with limewashed walls that go green with algae every year. Normally I fill my backpack with an anti-fungiside and spray/scrub the walls.
This year some builder has told her to clean the walls with sugarsoap
I'm guessing it's pretty alkaline and kills the algae. I don't fancy pumping standard sugarsoap through my pump cos it's full of granules.
Anyone else heard of this method? Don't like the sound of it myself so I've told her to try a test patch herself.