For optimal results, we recommend using all three products: Water Additive, Toothpaste Gel and Breath Freshener. But the choice is up to the pet parent to use one, two or all three. All three products feature the same dual enzyme systems. All three are truly brushless. If convenience is a key factor or your pet doesn't like to have their mouth touched, we recommend the Water Additive. If you have a program that works for you and your pet is still suffering from halitosis, try using the Breath Freshener. If you are comfortable flipping your pet's lip, then the Toothpaste Gel can be used and will provide maximum enzyme contact.