Homemade Dishwasher Detergent -- This recipe calls for buying liquid castile soap as the main ingredient, but I suspect making your own castile soap would reduce your cost even further. Going chemical free is awesome and all, but to me, in these tough times, the main reason to make your own cleansers is to save moolah!
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Make Your Own Dishwasher Detergent
Homemade Dishwasher Detergent Recipe