Dishwashing detergents; salts for use in machine dishwashers, namely, dishwasher additives for preventing limescale accumulation on the dishwasher and on glasses and dishes, and for increasing the cleaning power of dishwashing detergent; combination cleaners, fresheners and deodorizers for machine dishwashers; rinse agents for machine dishwashers; decalcifying and descaling preparations for domestic use