When should the water in an aquarium be changed?

When should you change the water in an aquarium?

Changing the water in an aquarium is essential for keeping your fish healthy. It also helps keep the water clean and removes toxic chemicals such as ammonia and nitrites. Even if the water looks clear, you might be surprised by the amount of debris at the bottom of the tank. Read this article to find out when to change the water in your aquarium!

Why should you change the water in your aquarium?

There are two reasons why changing the water in an aquarium is essential. First, it removes nitrates and phosphates. In addition to debris that you can see with the naked eye, other invisible natural waste products build up in the water. These are known as nitrates and phosphates. These substances are harmful to fish because they make them more vulnerable to disease. They can also stunt the growth of young fish and interfere with the reproduction of adult fish.

Regular water changes will also help restore certain trace elements that have been depleted over time. Plants, fish, and invertebrates consume certain trace elements such as calcium, potassium, iron, and others. Changing the water in the aquarium will therefore help the plants and animals in your aquarium obtain the nutrients they need.

Should you change the water in your aquarium every week?

Changing the water in your aquarium every week is an excellent way to prevent sudden fluctuations. Of course, the frequency may vary depending on the size, population, and setup of the aquarium. As a general rule, small, heavily stocked aquariums require more frequent water changes.

In any case, you will need to dedicate time to changing the water in your aquarium. Performing a complete cleaning once a month is not enough. Within four weeks, impurities can build up and harm your fish.

How much water should you change in your aquarium?

You should never change 100% of the water in your aquarium at once! We now know that this method can cause stress in marine animals. Experienced aquarium enthusiasts agree that it is better to change a small amount of water as often as possible. This partial change will not disrupt the balance of the aquarium.

For routine maintenance, it is therefore best to change a small amount of water. In freshwater aquariums, the rule is to change around 20 to 25% of the water each week. Adjust this according to your nitrate levels: less in a lightly stocked, well-planted tank, and more with goldfish or in a heavily stocked tank. But if you want a very precise indication, testing the nitrate level in your aquarium is the best solution, especially when you are new to aquarium keeping.

With this in mind, invest in a nitrate (NO3) test kit. Then, try to keep the nitrate level in your aquarium within the following range: 10 to 20 mg/L. As long as the nitrate level in your aquarium remains between 10 and 20 mg/L, perform small weekly water changes. If your nitrate level exceeds 20 mg/L, however, switch to larger water changes.

How do you test nitrate levels in an aquarium?

Although nitrate is not as toxic as ammonia or nitrite, its level should be monitored to prevent stress in fish.

To test nitrate levels in an aquarium, you will need the right equipment. If you are new to aquarium keeping and have a limited budget, we recommend test strips. This is an affordable, simple, and quick solution, as it takes only 60 seconds to get results for five parameters at once.

For greater accuracy, however, drop colorimetric tests are more widely used by experienced aquarium enthusiasts. To use this test, fill a small vial with water from your aquarium. Then, add a small amount of reagent. Depending on the color of the water, you can determine the exact nitrate level in your aquarium.

Our final tips for making water changes in your aquarium easier

If there is one thing to remember from this article, it is that the water in your aquarium should be partially changed every week (around 20 to 25% in freshwater aquariums). This is how you can ensure that the fish in your aquarium remain happy and healthy.

To make changing the water in your aquarium easier, place a marker in one corner of the tank. This will allow you to easily change the same amount of water each time. Finally, remember that the water temperature should be the same as the water already in the aquarium, or even slightly cooler.

And for even more tips and tricks related to aquarium keeping, browse our blog!