AmieSugat says November 21, 2012 at 2:31 PM Add equal amounts distilled/deionized/RO (or nikkon pHi-mag) water and vinegar. the chlorine and other chemicals found int unfiltered or carbon filtered water can ruin the essential oils and even make the mixture spoil or smell bad. the purer the water is, the longer your mixture will last before going rancid or spoiling.