Hard water can cause streaking and uneven color when dyeing. Calgon keeps calcium and other mineral in suspension; therefore, they will not interfere with the dyeing process.

Instructions
Use 1 cup/0.23 kg Calgon per washing machine load when dyeing in washing machine. Use 1/4 teaspoon/1.25 g per 8 fl oz/0.24 L dye solution in dye bath.