By Jimmytheone
United Kingdom 
Having problems with black spot on my paving slabs. I have tried power washer, Patio Magic and patio cleaner from Wilko. Have any members had success and what did the trick for you?
19 Aug, 2023
Same here, Jimmy,but ours are the slabs,used as a circular feature,and all the white marks are said to be Lichens,which are a natural occurance with this type of slab.. No amount of cleaning will shift them,as we have tried.. We just have to live with them..
19 Aug, 2023