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Is Spring Water Good For Fish Tanks?

is spring water good for fish tanks

Water is the most important part of an aquarium. You can use water from any source if it is suitable for use in an aquarium. But, can we use spring water in fish tanks?

Spring water is a recommended water source for freshwater fish tanks, but it can only be used as long as you understand a few things. The most crucial point to keep in mind is that not all spring water is created equal; thus, the mineral contents and pH levels of bottled spring water can vary from brand to brand. Most importantly, the pH of the water should fall between 7.0 to 7.8 to be considered safe and fish-friendly.

However, if you don’t want to run the risk, there are few other water parameters as well that you may require to test before you flood the branded spring water into the tank. “What are those parameters and how they are crucial anyway?” you may ask. Well, for that, you need to read through the following sections because we have it all here – everything you’ll ever need to know about spring water and its ‘safe’ use for fishkeeping.

Using Spring Water for Fish Tanks

Spring water, without a doubt, has been considered a safe water source for fish tanks. But the underlying catch that you need to understand is that bottled water labeled as spring water doesn’t necessarily make it fish-friendly. This water is also treated chemically in the factory which means you aren’t getting the natural spring water.

If you don’t know, there were some cases earlier that came into the light where it has been reported that bottled spring water brands that used to be marketed and advertised as ‘natural’ spring water, found to be heavily contaminated and had acidic pH.

There are many different brands in the market, and we don’t know where they get the water from and how they process it, therefore make sure that you don’t put blind trust in any new brand you came across lately. To ensure the well-being of your tank life, it’s a mandatory practice to check for the minerals and pH of the water before you decide to go for a certain brand.

Apart from the mineral contents that can vary from brand to brand, another drawback of using the spring water for fish tank is the price it sells for. Bottled spring water is the costlier alternative to tap water and is mainly used for smaller tanks only. So if you own a bigger aquarium and cherry on the top, you are adamant about using spring water as the primary source of water, your fishkeeping hobby is going to be expensive to pursue.

However, the primary reason why many betta tank owners prefer spring water over other sources because it’s reasonably safe to use (considering pH levels fall in the line) and doesn’t contain any amount of chlorine and other heavy metals.

When using spring water for the fish tank, pH should be your main concern because it already has the essential nutrients and minerals to keep fish healthy, and you don’t require to remineralize it. The availability of pH up or down treatments can be a plus point for you since it helps to alter the level to the safe ranges when needed.

You should test different brands for the following water parameters before you decide one to go for – which has all the requirements met and is easily accessible to you. Also, make sure to be consistent with one brand because switching with unfamiliar ones can give rise to nothing but unwanted problems.

Recommended Water Parameters for Fresh Water Fish Tanks

is spring water good for fish tanks

According to some aquarists, if you are using spring water for your fish tank, there is no need to check for any parameter besides pH. But in order to play safe, it’s suggested that when you use a new brand for the first time, kH and gH are other important water parameters (that completes the Bermuda Triangle of water chemistry) you should test to ensure proper water quality.

Understanding the aquarium’s water chemistry would help you determine and measure the right properties to match the fish’s needs.


pH refers to the water being either acidic, basic (alkaline), or neutral. A pH of 7 is neutral, pH below 7 is acidic, and a pH above 7 is basic. Even though different species of fish have different preferences for pH values, most species can adapt to a wide range. But as a fishkeeper, you need to keep in mind that even a slight change (suddenly) in the amount of pH can cause lethal stress to fish. For instance, a pH of 5.5 is 10 times more acidic than water at a pH of 6.5

Make sure to take care of these two aspects when dealing with the pH level of the water.

  • At any cost, avoid rapid changes (that is more than .3 units a day) in pH because it is stressful for the fish. You should focus more on maintaining a constant and stable pH in the tank instead of trying to get a certain value.
  • Most fish species are comfortable within the pH range of 6.5 to 7.5 and are also able to adjust somewhat outside of their optimal ranges if required.

gH (Carbonate hardness):

It helps in measuring the concentration of carbonates and bicarbonates in the water. kH is also used interchangeably with the term “buffering capacity,” but technically, they aren’t the same thing but are meant to be equivalent in the context of fishkeeping.

Buffering capacity is the water’s ability to keep the pH stable as it helps to neutralize the acids or bases when added to the water. Buffering can result in both positive and negative consequences; without buffering, the pH of the tank is likely to drop over time, and on the other side, having a high buffering capacity makes it difficult to lower the pH (in case if it’s too high) in the tank. So how much buffering does your tank requires?

The ‘test kits’ that assess the buffering capacity of an aquarium give results by measuring kH. The kH of the tank needs to be sufficient enough to prevent large pH swings because if it’s too low (less than 4.5 odH), you will have to put extra effort to maintain the stability of the tank’s pH. Make sure to increase kH or perform frequent partial water changes if you witness the pH getting drop by more than two-tenths of a point over a month.

Note: You don’t need to match fish species to a particular KH value because kH doesn’t directly affect fish.

gH (General hardness):

The general hardness of the water is the measurement of the dissolved concentration of magnesium and calcium ions. When we distinguish fish species for their preferences for “soft” and “hard” water, general hardness (gH) is what we refer to.

There are various methods by using you can increase and decrease the gH of the water, but it’s not recommended to do so unless it’s absolutely necessary for the survival of the fish. Since all three parameters (pH, kH, and gH) interact with one another to varying degrees, a small amount of change in either one may disrupt the whole water chemistry inviting more trouble for your aquatic pets. Therefore it’s considered critical for the new aquarists not to tamper with any of these water properties for the well-being of the tank.


We hereby assure you that if you mindfully take care of all the vital points, we have mentioned in this article, you will encounter no significant issues maintaining a healthy tank that would help your fish to not only survive but thrive.

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