I am looking to clean this patio along with the roof and house. Does anyone know what type of stone this is and is a surface cleaner ok on this type of stone. I plan to pre-treat with about a 5% SH solution. Most of the patio has green algae and some black mold/mildew. I don’t market for patios but the homeowner threw this in after I had already looked at the house with no intentions on doing the patio too. Any help would be greatly appreciated.
