Can I use softened water in my aquarium?

Some types of fish, particularly tropical and exotic fish, require special water conditions. Before filling a fish tank with softened water, we advise checking with your specialist provider. 

If you keep fish in an indoor aquarium or outdoor pond, check with the aquatics store where you bought them, or consult a vet or aquaculture expert. Softened water may not be suitable for exotic, ornamental or tropical fish because they can be affected by the minerals in either hard or soft water. Different choices of substrate and ornaments in the tank can affect the hardness level of the water, as well as the water supply itself.  

Water hardness measures the presence of calcium and magnesium ions in the water, as well as the amount of carbonates and sulphates. You might hear these called dissolved salts. Different species of fish need different hardness or softness levels. It’s common sense to try to provide them with water that meets their requirements, to nurture their long-term health.  

If you’re thinking of keeping aquarium fish for the first time, it’s a good idea to research their soft or hard water requirements first. For ease, you might decide to keep fish that prefer a soft water environment, if you have a water softener. 

In fishkeeping and aquaculture, water quality is an important specialist topic. You may need to dechlorinate tap water of any kind before adding it to your aquarium. As well as measuring aquarium water hardness levels, fishkeepers routinely monitor and control the temperature, pH and levels of ammonia, nitrite and nitrate, as well as other dissolved salts and minerals. You can buy test kits to measure all of these different components.  

Make sure the filter in your tank is regularly maintained and in good working order, to maintain consistent water quality for your fish.  

Our water softeners help you around the home in so many ways. Softened water can prevent limescale build-up in taps, pipes and appliances. Many people think it tastes better than hard water, and it’s much softer on skin. Get in touch with our experts to find out more about our 3 month no obligation trial. Request a quote.