In soft water, use 50ml Surf laundry powder for light loads, 90ml for standard loads, and 170ml for larger (or dirtier) loads. If you live in a medium water area, we recommend using 90ml Surf powder for light loads, 130ml for standard, and 201ml maximum for larger/dirtier loads. As for hard water, we advise using 130ml laundry powder for light, 170ml for standard, and 250ml maximum for large loads.