To remove calcium deposits from your dishwasher you can take a glass and fill it halfway with vinegar or even fill the glass full of white vinegar.
Then place the glass in the dishwasher on the bottom rack and the vinegar will splash around in the dishwasher and clean the calcium deposits from the dishwasher.
You can also add some vinegar to the detergent dispenser of the dishwasher and it will too clean the calcium from the dishwasher.
You can also add some CLR cleaner to the dishwasher detergent dispenser which is also very good at getting rid of calcium deposits in dishwashers as well.