Dishwasher detergent was one of the most expensive things we purchased each month. What is more, I didn't like our dishwasher all that much due to its
ghetto ancient status and cleaning ability. All this lead to washing our dishes by hand. Our dishwasher became a holding tank for the dishes until I could wash them, and was used sparingly. We still run it every 10 days or so, or when Jules is home by himself.
When I looked into homemade dishwasher soap I always had the same problems: 1) everyone complained they didn't work and left a filmy white residue, and 2) they contained Borax. I am personally a bit in love with Borax and use it to clean everything in our bathroom, as well as our Laundry Soap. The problem is Borax is extremely toxic.
While we are not sucking on our clothes after they have been rinsed and hopefully no one is licking any fixtures in the bathroom, we are putting our dishes in our mouths. If any residue does remain, I don't want to ingest it.
After some trial and error, we now have a dishwasher detergent which doesn't leave film and doesn't contain Borax. YAY!
Homemade Dishwasher Detergent
1 cup Castile soap (We use Kirk's)
1 cup citric acid
4 cups baking soda
2 cups washing soda
Grate the soap up on ultra fine and then pulverize it into a powder as best you can. Be sure you use a form of Castile which will dissolve well in cold water. We tried our Kirk's out in the sink before using it in the dishwasher just to be safe.
Once the soap is in as much a powdered state as possible, put it in a big bowl and mix in all the other stuff. I finally had to resort to mixing in my giant bread bowl so that I could be sure all the white powders were mixed evenly.
Fill up the soap container of your dishwasher with the detergent and then fill the rinse agent with white vinegar. The vinegar reacts with the baking soda during the rinse to clean any residue. The citric acid does the same thing as well as cutting through most gunk. Be sure you get granulated citric acid rather than lemon juice or another product which contains the citric acid. It only works when it has initial contact with water.
I have read in multiple places not to wash patterned dishware with citric acid. Since my vintage Pyrex is the only patterned dishware we have in the house and I love it beyond measure, I haven't tried it. I don't know if the warnings are valid, but just be sure. Metal seems to be fine, though I have seen warnings about that as well.
Important Info: If you want to make this dishwasher detergent, go out to the store quickly to purchase the citric acid. Now is the end of the canning season and general grocery stores will not only have the product on the shelves, but also have it for really cheap. At other times of year it is harder to find, though it can always be ordered through the internet.