my dishwasher is leaving scum on dishes tried everything to clean ?

The scum will be broken down food particles and or limescale.

Use dishwasher salt - change the detergent - use a good quality rinse aid - run a cleaning tablet through the machine now and again - rinse the worst of the food debris off the crockery before loading the machine - remove and clean the filters in the bottom of the machine - check for blockages in the rotating arms - avoid the multi tabs.

Rinse Aid breaks down surface tension in the water - helps any dirt to drain off before drying - no rinse aid and the dirt particles get baked on hard.

Peccavi
January 2011