Hypo was what I used in October, they called yesturday moaning it was green again and considering what they paid me it should have stayed cleaner longer
I told them I would treat it again but to be truthful I've thought about it and think they are being unreasonable, I cleaned their patio and it looked brilliant, the fact that it has turned green over winter is due to the environmental conditions not that I didn't do my job right..... the amount I charged is irrelevant
It's a bit like them complaining to a car wash a month later that their car has got dirty again.