Why Get an Automatic Dog Waterer? Automatic Pet Waterers are a great and healthy way to supply your pet with more water. Veterinarians have been encouraging pet owners to get their pets to drink more water for years. This is a simple and easy solution to the problem. Not only do they supply more water, but they keep it clean through the use of filters. Many of the waterers we sell use a patented free flow fountain style filtration system which keeps the water clean and oxygenated. Big Dog Drinkwell Automatic Dog Waterers are great for larger pets. This Drinkwell fountain has been designed specifically for larger dogs, and holds over two gallons of water so your pet is sure to be well hydrated.