We use: Grapefruit seed Extract. H20, carmal extract, xylotol for sweetness -- found in sugar free gums. A solution of 20 drops Grapefruit Seed Extract with 10oz. H20 and carmel extract for taste has cured incoming dogs to the pet rescue of bad breath and tarter build up. This took about 2 days of having it sprayed into the mouth for bad breath and a week to notice loss of tarter. Daily maintenace of 4 drops in water also showed a reduction in weight in our heavier dogs. Give chew toys or carrots to dogs during this time to assist with the cleaning process. GSE is an excellent anti bacterial element and has many uses for people and pets. Great for raising the pets PH level as well.