I love love love my homemade laundry detergent the only thing I added to yours was 1 bucket
of oxiclean and 2 containers of unstoppables any scent I love the purple one.
Fill it with your normal amount of detergent and a hefty scoop
of oxiclean (or whatever detergent booster you prefer).
One method that works well for prefolds is to place them in a pot of boiling water with a bit
of Oxiclean.