Is Hard Water Bad for Betta Fish? Let’s Read to Get the Answer

Betta fish are small, seductive, colorful, and easy to care for, making them favored by many fish keepers.

Clean aquarium water with perfect DH and pH is vital for your Bettas. When all factors in your aquarium are well, you can expect your fish will be highly active.

Regarding water hardness, have you ever wondered, “Is hard water bad for betta fish?” We will discuss the topic in detail. Let’s scroll down for more information.

Is Hard Water Bad for Betta Fish?

Betta in small tank

Hard water is not bad for betta fish, but bettas prefer softer water. So we recommend keeping the DH less than 25.

The DH (the degree of hardness) of your tank water is the measurement of the mineral salts in your aquarium tank. It is easy to determine the DH of your tank water with accurate aquarium test kits on Amazon.

The ideal DH for bettas is under 25. So if it rises above 25, a simple solution is to add distilled water, which you can find in any grocery store. All you need to do is add a little at a time and recheck, and it will quickly bring the DH under 25.

Other Betta Fish Tank Conditions 

Once you’ve set up your aquarium and placed the substrate on the bottom along with your decorations, it is time to add water.

The tank water must have a specific temperature, DH level, pH value, and more to ensure that your bets are in an environment that supports them thriving.


The ideal temperature for bettas

The natural habitat of bettas consists of warm water. It is essential to mimic this environment as much as possible. 

We recommend keeping the tank water temperature between 76°F to 82°F. If you let that condition persist, your bets will become ill and may end up dead.

Proper tank water filtration is essential as it will help maintain the ideal temperature for your bettas. 

Once the temperature condition in your aquarium is perfect, your bettas will be playful, eat voraciously and showcase brilliant color on their bodies.


Although chlorine is commonly used to kill harmful human bacteria in water, it can be lethal for your bettas.

Before adding these fish to your tank, you must treat your tap water using bottled chlorine bleach, which you can find in many aquarium supplies or pet stores that sell fish. It is a simple process, and you must follow the instructions.

PH Values

Testing pH value refers to measuring the acidity and alkalinity of your aquarium water. Initially, you must test the pH before adding bettas to your aquarium.

The ideal pH for bettas is 6.5 (slightly acidic), although a value of 7 is also acceptable. When adding other fish to your tank, you must find out about them to make sure they acclimate well to the same pH level.

6 Water Types for Bettas And How to Use Them 

The following are six common water kinds that will work for your betta tank.

Betta-Specific Water

Many mistakenly believe this water type can be used as a shortcut for new betta tanks. But remember that it doesn’t contain beneficial bacteria. The only thing you get is plain water with a conditioner added to it.


Rainwater is a controversial water when it comes to betta aquarium use. Many points to pollutants and high nitrogen content as reasons to avoid its use. 

We recommend avoiding using rainwater in your fish tank if it’s from a thunderstorm since that is when nitrogen levels are very high. 

Also, remember to test the water parameters, then adjust them if needed. It also needs to filter through activated carbon.

Spring/Bottled Water

Bottled or spring water typically goes through at least one filtering process to ensure it’s safe for human consumption. So it is pretty soft.

Distilled Water 

This type has removed all its minerals, which is not good. The reason is that your fish need basic minerals to stay alive.

You can use it in an emergency where the pH level is too low or high. It is alright to use it to reduce the hardness quickly.

City/Municipal Tap Water

This water is typically treated with chlorine, chloramine, or other chemicals to ensure it is free of disease-bearing organisms.

But these chemicals are deadly to bettas and other tropical fish. So you can buy a water conditioner that will neutralize those chemicals and make them safer for your fish.

Cycling Water For A New Betta Tank

gorgeous betta

You should do a 20% water change per week, while others increase it to 50%. All these water changes can be very harmful to fish for some reasons.

Every time you remove the water from the tank, you also remove the slime that the fish sheds as they swim around, helping prevent bacteria from reaching the fish’s scales and internal bodies. 

Second, every time you suck water out of your tank for new water, you will stress the fish. So it is best to make sure the parameters and water temperature are as stable as possible. We recommend a 20% water change every two weeks.


Do My Bettas Eat Plants?

Bettas prefer to nestle among the leaves to rest, but they don’t like to eat plants. 

Some report that betta fish nibble on a plant for food, but that is not true. These fish require meaty foods and aren’t plant eaters in nature. 

Yes, if they have no choice, they will nibble on the plants. But plant matter is not the ideal food for betta fish.

Do Bettas Prefer Soft or Hard Water?

They prefer soft water.

How Do You Fix a Betta Fish With Hard Water?

Just add distilled water to your tank.

How Is Water Hardness Measured?

You can measure water hardness with accurate aquarium test kits.

What Kind of Water Is Best for Betta Fish?

Spring water and tap water are the best types of water for your bettas.

Can I Change My Betta Fish’s Water

Most experts recommend changing your betta’s water once every two weeks.

The Bottom Line

Is hard water bad for betta fish? The short answer is No, but they prefer softer water. Therefore, you should keep the DH less than 25.

If you have any other queries regarding these beautiful little fish, comment or check out other posts. Thanks for your time!