About a year or so ago, we noticed that our dishwasher wasn't getting dishes as clean, and the glassware was becoming cloudy. After some research, we discovered that the powdered detergent that we had been using had been reformulated to remove most, if not all, of the phosphates - a substance that both softened the water and helped remove the food traces. At this point, we switched to liquid detergent, but I never really liked the liquid. It's messy, expensive, and wasteful, when you consider how much remains in the bottle even after it's 'empty'. So...after a little bit of internet and home research, we found a formula for homemade dishwasher powder that works just fine and is still environmentally friendly/phosphate free.
Mix well together:
1 c. powdered borax
1 c. washing soda
1/2 c. fine Kosher salt
1/2 c. citric acid (aka sour salt)
Store in a tightly lidded jar or plastic container, labeled for safety's sake.
Use 2 T per load.
Notes: The borax and washing soda can be found in the laundry aisle of your supermarket (check the bottom shelf - they're not high margin, glitzy items, so they're hidden down here). Kosher salt is with the salts, natch - usually you can find coarse as well as fine - get the fine. The citric acid is a little trickier to find, but many bulk food stores carry it, as do spice shops. It sometimes is with the Kosher foods as well and is used as a preservative as well as to add sourness to certain foods. Expect to pay about $5/lb if you buy it in bulk.)
In case you're wondering, the borax acts as a water softener and helps to reduce the cloudiness/spots as well as helping with food particle release from the dishes.