You can also reduce the initial foaming during mixing by adding water to your container first and then adding the appropriate amount of star san. Careful rocking will mix the solution completely. The maker of star san said in an interview on The BN to always add the chemical to water, never add water to the chemical. Then you can reduce the foaming again when you empty the container by either racking (which also sanitizes the racking cane and tubing) or pouring SLOWLY. Don't fear the foam, yes, but also play nice with star san and there won't be as much foam.