My vet gave me a oral solution to add to my babies water. It's supposed to cut down on the bacteria in their mouths. I add about a teaspoon to a quart of filtered water and keep it in my refrigerator to replenish their supply daily.
They LOVE it! They drink so much more water now than they did before I started using this solution. It doesn't have any odor, and there's so little in a large amount of water. But GEEZ, they drink like there's no tomorrow. When I asked the vet, he said that it's not supposed to make them thirstier or anything, they must really like it.