Roxil 100 Wood & Patio Cleaner is a biocidal cleaner designed to remove algae and mould from exterior surfaces such as decking, fencing, sheds and patios. Once applied to a surface, the biocidal ingredients within will kill mould, algae and lichens whilst the cleaning surfactants will help to lift and remove dirt. Simply spray onto the surface and let Roxil work its magic over 1 - 2 days.