I just moved into my new apartment and the dishwasher is leaving a gritty substance on my dishes! I am using Liquid diswasher soap (Calgon). I have run a bottle of "Dishwasher Magic" thru the machine but it has not made a difference. I think whoever was here befor me used powdered soap and it has builot up inside the machine. How do I get it clean? Is there a way to take it apart on the bottom to see if there is anything stuck or built up inside someplace? I need help!