I bought this product because I moved to an area where the water is quite hard (northern France) before I was in the Paris suburbs. I stopped putting so Calgon. For two weeks I saw a light white veil around my rubbery window. So strange! I was advised where I live to this but I wonder if I will not recover from the Calgon and remove this device to see the difference! It is written that it is also good for the dishwasher, by cons a technician who told him that a dishwasher, it was useless because he had put salt in the dishwasher mandatory. In short, so I do not take this item for the dishwasher and do not see no white marks on the inside or on the dishes. I'll see with time for the washing machine but it is true that I find the machine by cons, much softer even without Calgon! It is still strange: D
