They may be marketed as “low maintenance” devices, but pet fountains require regular cleaning just as ordinary water bowls do. Individual units vary, so follow the manufacturer’s instructions. Regardless of the model, you should clean the water basin and water reservoir every day, and disinfect them both every few weeks. Doing so will help to keep bacteria levels low, which will make cleaning easier and will make the waterer healthier for your pet. Don't worry about doing it the easiest way; worry about doing it right.
Manufacturer's Manual
Commercial products that tempt your terrier with moving water vary in design. Some discharge water like human water fountains do, while others force air through the water, creating a rippling surface. Most have a removable reservoir and bowl as well as an internal motor, but some attach to a hose and use the pressure from the spigot to move the water. In all cases, follow the manufacturer’s directions from cleaning the unit, but maintain a strict schedule.
The Need for Clean
Wet, warm, sitting on the floor and periodically in contact with your pet’s mouth, Fluffy’s water bowl provides a perfect habitat for a bacteria bloom of epic proportions. Healthy dogs have robust immune systems capable of dealing with the ubiquitous bacteria surrounding them, but microbe-laden water can make even healthy dogs very sick. Pets can carry and distribute the bacteria all over your house, subjecting your family to potential pathogens.
Methodical Maintenance
No matter what type of water bowl or fountain you provide your canine companion, you must clean it regularly -- preferably every day, but every other day is acceptable. To do so, remove the water basin and wash it thoroughly with soap and water. Even though Spot is a member of the family, wash his dishes separately from your family’s dishes. Unless directed otherwise in your fountain's user manual, scrub the bowl with a clean washcloth or soft scrub brush. Be sure to rinse it well before you refill it and place it back in the unit. If your fountain uses a water reservoir, wash it at the same time you do the basin. Clean any internal components as directed by the manufacturer.
Sterilize for Your Pets’ Lives
Even with daily or every-other-day cleanings, your pet’s bowl may become a haven for resilient pathogens. Combat these microbes by disinfecting the bowl periodically with a mild bleach solution. Soak your pets bowl in a 1 percent bleach solution for about 10 minutes. Repeat this process every few weeks. Before returning the bowl to your dog, be sure to rinse it thoroughly.