Now, run one more cycle with nothing inside except a cup of vinegar on the top rack. This is a “deep clean” cycle, so set it to the longest, hottest setting. Add a squirt of lemon juice to the vinegar for a fresh scent—because your dishwasher deserves to smell like a lemon grove, not a pickle farm.
When the cycle finishes, open the door and do a little victory dance. Seriously, shake your hips. Your dishes will thank you, and your glasses will come out so clear you could read a newspaper through them. Well, a tweet-sized newspaper anyway.
How To Clean Limescale In Dishwasher at Rudolph Miller blog
If you still see spots after all this, don’t despair. Sometimes hard water is really stubborn, like a toddler refusing to eat broccoli. In that case, consider using a commercial dishwasher cleaner or a rinse aid designed for hard water. But 9 times out of 10, this double-whammy of vinegar and baking soda will save the day.
