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Home > Cats > How Often to Change the Water in a Cat Fountain: Vet-Approved Advice

How Often to Change the Water in a Cat Fountain: Vet-Approved Advice

cat looking at water fountain

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Dr. Alice Athow-Frost

Veterinarian, BVM BVS MRCVS

The information is current and up-to-date in accordance with the latest veterinarian research.

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It never seems to be a problem with dogs; they’ll drink water from anywhere, including puddles on the sidewalk and the sink if they can reach it. But cats are different. You may not see them drink from their bowls often. Some pet owners have found that a water fountain encourages them to consume more liquid, which can keep them hydrated and healthy.

Cat water fountains keep the water moving, which makes them more enticing to felines. Many also have large capacities that are well over what your pet should drink weekly. However, that doesn’t mean you shouldn’t change the water frequently, even if they have a filter. So, how often do you really need to change the water to keep it fresh? At a minimum, once every 5 days, but we recommend it more frequently if you have more than one cat.


Cat Water Fountains

Cat water fountains work by circulating water through a filter, usually containing activated charcoal. A pump provides the power to keep it moving. The premise is that the sound of the running water will encourage your pet to drink more often, as running water is usually fresher water (in the wild). Several factors will influence how much your cat should drink, including their life stage, activity level, and diet.

The frequency of changing the water lies with its cleanliness. The filter will help clean the water of debris which will reduce the bacterial growth.  It will also filter out chlorine, heavy metals and pesticides (depending on the filter type you use) but the filter won’t get rid of bacteria that will inevitably grow. We must also think about the fact that a playful adult cat or kitten will undoubtedly play with the stream of water, further contaminating the water. Some cats enjoy a drink straight after eating, so food contaminants will enter the water. It’s these factors that might make you consider changing the water in their fountain daily.

longhair cat drinking water from a pet drinking fountain
Image Credit: Lightspruch, Shutterstock

Wild Instincts

You may wonder why a water fountain would be necessary. After all, cats can obviously sense when they’re thirsty. It’s more complicated than feeling the need to drink. Our pets are descendants of the African Wild Cat (Felis silvestris lybica) which has a very wide distribution.  It is found throughout most of Africa, southwest and central Asia into India, China, and Mongolia. This feline migrated to other areas during the ages, occupying various but marginal habitats. Water is often scarce in these places, so the African Wild Cat, and thus our domesticated cats, evolved to manage with minimal water supply.

The other factor is the species’ feeding habits. Felines are obligate carnivores, meaning they cannot meet their nutritional requirements through plant proteins alone; they need animal proteins to survive. Their natural diet (mainly consisted) of freshly caught small rodents which used to fulfill most of their water needs, so this impacted the cat’s drive to seek water. It’s worth noting that our domesticated cats have hardly evolved from their wild predecessors with changes in only 13 genes reflecting the influences of domestication, so their drive to drink water is still low even though their diets have changed hugely in domestication.

Evolution and adaptation to a desert-dwelling lifestyle has allowed felines to adapt physically to get most of the water they require from their carnivorous diet. However, domesticated pet cats are not usually fed whole, fresh carcasses, and therefore are required to drink more, especially if they are fed a kibble diet.  A water fountain can tempt a domestic cat to drink more often, helping to keep them hydrated and healthy.

Proper Hydration

The other consideration of how often you change the water in a fountain is a cat’s hydration needs and how often they use it.  Your kitty should get about 4 ounces of water per 5 pounds of body weight. However, that figure varies depending on your pet’s diet. For example, canned foods can contain 70–80% water, which can go a long way toward meeting your cat’s daily needs.  Therefore a cat eating wet food is likely to only visit the water fountain occasionally.

Conversely, feeding your pet strictly dry food will increase the amount they should drink since dry diets typically contain only 10% moisture. Therefore, usage will play a role in the maintenance of a water fountain, and the speed at which the water gets dirty. It also is a factor when deciding what size to get. Don’t let the amount of fluid be the only condition for changing the water. The less you refresh it, the more likely it is for bacteria to develop.

cat water fountain
Image Credit: Vershinin89, Shutterstock

Using a Cat Water Fountain

We suggest getting your pet used to the fountain without the circulation feature first. Some cats are wary of anything new in their environment, let alone something with moving water. Once your kitty seems comfortable with the replacement, turn on the fountain. If your pet is scared of it, give it another go later. After all, it’s essential that they drink enough clean water so we don’t want to scare them off completely!

You might consider leaving the regular water bowl out and running the new fountain at the same time. Curiosity may get the best of your cat, and at least get them to explore it on their timeline.

Finding a great water fountain that you and your cat will both love is harder than it sounds.

Hepper Stainless Steel Cat Water Fountain
1 Reviews
Hepper Stainless Steel Cat Water Fountain
  • Premium 304-Grade Stainless Steel - This metal cat water fountain is hygienic, with superior...
  • Serene & Healthy Cat Drinking Fountain Experience - With whisper-quiet pumping & an advanced...
  • Say Goodbye to Dehydration - Provide your cat with a constant source of flowing water with this...

We recommend Hepper's Stainless Steel Cat Water Fountain, a beautifully designed option with triple filtration, adjustable flow modes, and a conveniently large capacity. This fountain is easy to clean (many parts are even dishwasher-safe!) and sturdy enough to last for years. 

At Pet Keen, we've admired Hepper for many years, and decided to take a controlling ownership interest so that we could benefit from the outstanding designs of this cool company!


Final Thoughts

A cat water fountain can provide enrichment for your pet’s mental well-being and an enticement to drink more often. It’s helpful for cats that eat a dry diet to ensure they get enough fluids. Proper hydration will help keep your kitty healthy. It’s essential to keep the product clean. We recommend a full clean and water change every 5 days, and changing the filter in line with the manufacturer’s guidelines. If you have more than one cat, you will need to change the filter, the water and clean the fountain more often. If the water is ever looking dirty, don’t wait for the 5 day mark, make sure you change it immediately.

Featured Image Credit: Bianca Grueneberg, Shutterstock

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