Why is my aquarium water getting cloudy?

Why is my aquarium water cloudy? What makes aquarium water cloudy? If you have owned an aquarium for a while, you may have already experienced cloudy water.

In this guide, we will explain why this happens, discuss the causes, and above all, show you how to treat cloudy water in an aquarium. 

Why is my aquarium water cloudy?

When you enjoy admiring your aquarium, there is nothing more annoying than cloudy water. But how does this happen, and what causes it? It can be difficult to answer this question. However, we can list the various problems that cause cloudy water and how to solve them. But first, learn to determine whether your water is grayish, brown, or green. This way, you can apply the appropriate solution.

Why is my aquarium water cloudy?

Have you just bought your aquarium and filled it with water? Then the first factor contributing to this cloudy appearance could be the substrate you are using. 

1. Substrate

In freshwater aquariums, all substrate must be thoroughly rinsed before being placed at the bottom of the aquarium. This is because substrate can be extremely dusty if not thoroughly rinsed, causing cloudy water. The best way to prevent this is to rinse the substrate in small quantities to ensure it is thoroughly cleaned. If this step is skipped, the combination of dust and water will inevitably cause cloudy water. 

2. Tap water

Cloudy water can also be caused by the type of water used. Tap water can contain heavy metals, nitrates, phosphates, and even silicates. Remember to test your tap water before adding it to your aquarium to ensure that its nitrate and phosphate levels, among others, are not too high. 

You can also use a tap water conditioner. This will neutralize harmful elements such as chlorine, chloramine, ammonia, and heavy metals. Finally, we recommend letting your water sit out for 24 hours before pouring it into your aquarium. This will allow all the chlorine to be naturally removed. 

3. Bacterial colonization

After setting up a brand-new aquarium, it is not uncommon for the water to become cloudy. This is due to the colonization of bacteria that convert nitrogen to oxidize ammonia and nitrites. This beneficial bacterial bloom can also occur in any aquarium if there is a sudden increase in nutrients. 

An increase in nutrients triggers the growth of heterotrophic bacteria. These bacteria break down fish waste, plant debris, and uneaten food into ammonia. They then create a slimy biofilm that sticks to decorations and the aquarium walls. In this case, try reducing the amount of food and performing more regular water changes. Adding live plants can also help reduce nutrient levels.

4. Driftwood

When your aquarium water turns brown or green, it negatively affects its appearance. This can be caused by adding a popular aquatic decoration: driftwood.  

If the wood has not been washed before being added to the aquarium, it can cause the water to take on a slight brown tint. This coloration comes from the release of tannic acid. It will gradually lighten with regular water changes and the use of a filtration system. If driftwood has been added and you notice a brown tint, test the water's pH level (tannic acids can lower the pH).

5. Algae bloom in the aquarium 

Of all the causes of cloudy water, green water is the hardest to correct. Green water is caused by a bloom of algae cells. These contain flagella that give them mobility, allowing them to swim closer to the light for photosynthesis. These organisms can occur due to: 

• Too-intense light;
• Overstocking with fish;
• High phosphate levels;
• Too many nutrients. 

These algae can disrupt the water quality. Not only do they discolor the water, but they can also deplete oxygen levels at night. 

How can you get rid of green algae?

Unfortunately, simply performing a water change is not enough to get rid of green water in an aquarium. To eliminate it, reduce nutrient input, use a UV sterilizer, and add Daphnia (water fleas) to the aquarium.

Conclusion: a solution for every problem! 

As you have seen, every factor that can cloud your aquarium water can be controlled. We hope you have succeeded in determining the source of the problem. Now you are able to prevent this nuisance and treat discoloration problems in your water. In a few months, you will be able to admire the beauty of your marine ecosystem in clear, crystal-clear water!

And for more tips and tricks on fishkeeping and aquascaping, we invite you to discover our latest blog posts.