£6.79 inc VAT HG Algae and Mould Remover is an effective algae remover. Overtime, algae and mould can build up on patios, walls, roofs, and all types of concrete outdoors. This effective algae cleaner makes your patio cleaner and your life easier. It provides results within 36 hours and has no harmful effect on grass and plants when diluted. Sufficient for surfaces of up to 200m². Add to Basket Quantity