I predict that some of you are already rushing to comment that this has not worked for you. In all my reading on the web, there are a lot of dissatisfied dishwasher owners. Even with the commercial soap. (You'll want to read my article on Keeping Your Dishwasher Clean to get my thoughts on scum that builds up inside these automated washers. A lot of people are making big mistakes, such as using a rinse aid when they may not really need one.) The issue isn't just the soap, but it's the water that goes through the appliance.
I'm going to give you the recipe I use, keeping in mind that I have a water softener. I'm finding that it works for me pretty well, but I had to try a couple of different recipes before I got one that worked just right. This isn't a "one-size-fits-all" kind of a thing. I suggest that you make a small batch of the recipe that follows, adjusting the ingredients as needed until you come up with the right formula for your water situation.
The Ingredients
Washing Soda:
Sodium carbonate can be used as a pH regulator to maintain stable alkaline conditions and to neutralize the acidic effects of chlorine and raise the pH level. Without using washing soda, additional detergent is needed to soak up the magnesium and calcium ions. It effectively cuts oil or grease on dishes and is used as a descaling agent in boilers such as found in coffee pots or espresso machines, which leads me to think it would do the same in a hot dishwasher.
Baking Soda:
Sodium bicarbonate can be added as a simple solution for raising the pH balance of water (increasing total alkalinity) where high levels of chlorine (2-5 ppm) are present. A paste from baking soda can be very effective when used in cleaning and scrubbing. For cleaning aluminium objects, the use of sodium bicarbonate is discouraged as it attacks the thin unreactive protective oxide layer of this otherwise very reactive metal.
*Note that this is very similar to washing soda and many recipes interchange this ingredient. If one doesn't work well for you, try the other. I found the washing soda worked best for me.
Borax:
Sodium borate is used to help cut grease, reduce spots and film by conditioning the water, and removing hard water minerals. It also works as a disinfectant. This is the one item that I would caution you to keep out of reach of little ones. It is mined from the ground and is a natural mineral, but not safe for ingestion. I took a tour of the 20 Mule Team plant in Boron, California, and was amazed at all the uses this product has in our everyday lives (and we aren't even aware of it)!
Citric Acid:
Citric acid's ability to chelate metals makes it useful in soaps and detergents by allowing these cleaners to produce foam and work better without the need for water softening. It also will remove hard water stains from glass without scrubbing. In addition, it works as a natural antimicrobial agent. I recommend purchasing Frontier Naturals one pound bag of Citric Acid from either Amazon, Frontier Naturals, or a food co-op. It will run you about $7-9, but should last a while. I wanted to get started right away, so I purchased some Fruit Fresh, which has some citric acid in it (or you could buy cheap lemonade packets), but it cost me more and I don't recommend this unless you're in a bind. However, it seems to be working well. I'll be ordering bulk citric acid from the co-op in the future!
Salt:
A lot of recipes for homemade dishwasher soap include salt, but I'm not sure that it's really a necessary ingredient. While it is often thought to reduce the effects of hard water, I've read elsewhere that adding salt along with the detergent does not soften the water much, but the water will gain some additional ability to dissolve hard water ions. How much is the question. Keep in mind that as water drops remaining on the dishware evaporate, deposits of the salt will likely remain. To combat this, the use of a rinsing agent such as vinegar will help eliminate the spotting. *If you should choose to use salt, do not use regular table salt, but rather course Kosher salt. Read more here.
Homemade Dishwasher Soap
{soft water recipe}
1/2 cup borax ($.18)
1/2 cup washing soda ($.33)
1/4 cup food grade citric acid ($.66)
* for hard water, try increasing the amount of borax or add 1/4 cup course kosher salt, not regular salt! Read more here and scroll to middle of the page where it says "Dishwasher Salt".
Combine ingredients and use sparingly. I use only about 1 to 1 1/2 tsp. per load. (For hard water, you may need more.) Keep in a handy container near your appliance.
Total cost: $1.17 per batch (mine was actually closer to $2.01 because I used the expensive citric acid).
Total # Loads: 81 per batch (@ 1 1/2 tsp. per load)
Total Cost Per Load: $ 0.014 - Nice!
Rinse Aid: Add white vinegar to the appropriate dispenser. Refill as needed. (I do this even for my soft water).
I'd like to hear your thoughts on this, so join the conversation and leave a comment!
