I have started receiving more calls to clean stucco houses we are having to mix a 3% solution and I'm still not satisfied with the results thankfully the customer is. Any advice would be appreciated. Sometimes I have encountered a clay type substance reddish in color a lot of the times this has been found on newly constructed homes is there something we can use to make this go away?

Do you have any pictures of this Ed?

Red dirt requires an acid and hot water works the best