Can You Use Spring Water in a Fish Tank?

Many people might think that using spring water in a fish tank is perfectly fine. After all, spring water is more natural than water from the tap, so it has to be safe, right?

While true spring water has many benefits for humans and fish, underground water is not the same quality it once was. Can you use spring water in a fish tank? Sure, but you have to treat it first.

Why Does Spring Water Need to be Treated?

Spring water comes from a natural underground and rises to the surface, coming out of the ground in a spring where you can collect it. Most spring water is rich in minerals and other elements, including potassium, calcium, sodium, and magnesium.

When spring water travels over and through rocks underground, the minerals from the rocks dissolve into the water. When there are a lot of minerals present, the spring is usually called a mineral spring. If a spring contains a lot of sodium carbonate or salt, it’s called a soda spring.

As you can see, spring water has a lot of benefits. But, much as it is affected by the minerals in the rocks it passes over, it is also affected by where it comes from and the path it takes underground.

For example, if the water runs through a heavily developed area, pollution may seep into the ground and get into the water. Other things, like how hard the water is and its pH, also charge depending on where spring water flows.

Ultimately, every spring is different because each has a unique source and path it follows. But you should always err on the side of caution and treat any spring water you plan to use in your fish tank.

How to Treat Spring Water for Aquariums

The first thing you should do is prepare your fish tank. Not only should you rinse the inside of the aquarium, but you should also rinse any decorations, rocks, and gravel you plan to place in the tank.

Then, it’s time to treat the water. But you can’t treat the water unless you test it first.

Three main things you need to check are the spring water’s pH, hardness, and carbonate and bicarbonate. You can usually get testing kits for these parameters at the pet store.

All fish have a pH preference, so it helps to have some idea of what fish you’re planning to put in the tank and what pH level they prefer.

If the pH is high, there are a few options for how to lower it, including chemical treatments and natural wood tannins. If the pH is too low, you can increase it by adding baking soda, crushed coral, or gravel.

The minerals in spring water are another problem. Some minerals are good for your aquarium, but when there are too many, they can be harmful to your fish. To make sure spring water doesn’t have too many heavy metals, the best thing to do is use a reverse osmosis filtration system.

Reverse osmosis gets rid of as much as 99 percent of impurities, including heavy metals and pesticides. If you want to use spring water in your tank, this is the best way to make sure it’s safe.

After the water is purified, you may also want to consider a water conditioner. A water conditioner will make the water more comfortable for your fish and make the transition to their new home safer.

Other Options

While you can use spring water in a fish tank, it takes a lot of work to prepare it appropriately. If you want something that’s more suitable for an aquarium that won’t take as much time to prepare, there are other options:

Tap water. Most tap water is treated and free of the most dangerous bacteria and other harmful particles, but this varies drastically depending on where you live. If you go with tap water, be sure to use a dechlorinator as the chlorine in tap water is toxic to fish.

Well water. Well water is similar to spring water in that its quality depends on the source. Well water can contain a variety of contaminants, and you will need to test and treat it thoroughly before using it in a fish tank.

Rainwater. Rainwater is an okay option, but it also requires testing and treatment. Rainwater is generally low in minerals and can easily become polluted. Plus, any rainwater that you collect from a roof or gutters may be contaminated with anything it picked up from running down these surfaces.

Water That is Not Good for Fish

Generally, you should avoid bottled water and distilled water.

Bottled water comes from many sources, but it can be well water or spring water. It’s likely been heavily filtered and may not have any benefits for your fish. It’s also extremely expensive and impractical for filling an aquarium.

Distilled water is very pure, but it is stripped of all of the valuable minerals that your tank needs. If you go with distilled water, you will have to add minerals back into the water first. Distilled water is also a little impractical as you need many gallons to fill up a tank.

Final Thoughts

Can you use spring water for a fish tank? Yes, but not straight from the ground. Spring water requires a lot of testing and adjustments to make it a suitable home for your fish.

The natural minerals are great for your tank, but make sure you check and adjust the pH, hardness, carbonate, and bicarbonate. You should also run the water through reverse osmosis filtration and condition it before cycling the tank and adding your fish.

That said, almost any type of water that you use needs a little care and attention before adding it to your tank. If you prefer the natural minerals in spring water and are willing to do the work, this can be a great option for your aquarium.