I have white spots, what are they and will Monty clean them too?

White Spots are an a organic growth known as Lichens which is a physical growth on the surface, unlike black spot which is below the surface. Monty Miracle Patio Cleaner will neutralise white spots and, over time the white spot will break down with the natural elements, in this case the solution will not be an instant removal but it will give you results over time.