1 cup borax – available in the cleaning aisle of most grocery and hardware stores
1 cup baking soda
1/4 cup salt
1/4 cup citric acid – if you can't find food grade citric acid, you may substitute two unsweetened lemonade packets
For each load (make sure the machine is full each time), put a tablespoon of this mix into the detergent compartment and fill the rinse dispenser with white distilled vinegar.