The dishwasher salt is used to remove the hardness of mineral ions (i.e. Calcium & Magnesium) from the water. Since Singapore has low water hardness that means low concentration of Calcium and Magnesium ions therefore the dishwasher salt is not required in using a dishwasher in Singapore.   For more information on things to consider before buying a dishwasher, check out Electrolux Dishwasher Buying Guide .