Why Is My Fish Tank Cloudy?

Why Is My Fish Tank Cloudy?

If you love having a fish tank in your house, it is essential to know how to take care of it. Not only does it ensure the well-being of your fish, but it also keeps the tank looking clean and healthy.

The health of the fish is your responsibility, and it can be disturbing if they become sick or die. Therefore, make sure you check your aquarium whenever you are at home.

One common thing that you may have noticed is that your fish tank keeps getting cloudy. No matter how many times you change the water, this keeps happening. There’s no reason to worry, as it can occur in any fish tank.

However, it is important to know what is causing the water to go cloudy. You have probably asked yourself the question why is my fish tank cloudy.

Let’s look at why your fish tank looks cloudy and how you can keep it clean.

What Causes My Aquarium to Be Cloudy?

Even if you have purchased a new aquarium, the chances are that it becomes cloudy after just a few days. However, this isn’t an emergency, so there is no cause for alarm. Your new aquarium becomes cloudy because this is the first time it has become a habitat for sea life. Microscopic organisms are beginning to make their home in the aquarium.

Moreover, nitrifying bacteria also replicate inside the water once marine organisms inhabit it. Its job is to clean up the water and maintain balance. But, it doesn’t start doing its work so soon. This is why the bacteria and microbes inside the water start to replicate rapidly. They are what you see causing the cloudiness in the water.

Additionally, you can contribute to the situation by adding too many fish or too much fish food. The food is not only enjoyed by the fish, but the microbes also feed and thrive on them. As a consequence, your water will keep clouding up for a while.

What Should I Do About It?

Naturally, you would want to do something to fix your aquarium if it becomes cloudy. A cloudy aquarium seems like a big problem, but it is not as serious as it appears.

The proper course of action will fix the situation. But, what’s more important is to prevent your aquarium from becoming cloudy rather than doing something afterward.

Let’s have a look at some methods to correct the cloudiness in your fish tank.

Leave It Be

You might be surprised, but one effective remedy for a cloudy fish tank is to do nothing. Let the beneficial or nitrifying bacteria take their time to grow in the water. Once they finally grow in number, their count will exceed those of the microbes that cause the cloudy water. These good bacteria start to eat the nutrients and food in the aquarium.

You might think that changing the water in your fish tank would solve this problem. But, a water change brings with it a new supply of nutrients. These nutrients become growth food for the microbes and cause them to replicate and cloud up the water once again.

However, leaving the water alone will facilitate the growth of nitrifying bacteria, which will kill the cloudy water bacteria. This is known as the cycling process and is a natural way of treating cloudy fish tanks.

However, you need to be careful during this process. The nitrite and ammonia levels can also increase if you leave the water for a while. Therefore, it is always wise to get the water tested for ammonia and nitrate and ensure that the levels are zero or negligible.

Moreover, don’t try to clean the filter too often, killing the beneficial bacteria.Why Is My Fish Tank Cloudy

Adding Live Plants

Another excellent method to remove the cloudiness inside your fish tank’s water is to add live plants. These plants harbor good bacteria and other microbes, which take care of the harmful bacteria and maintain stability in the aquarium. In addition, they help restore your aquarium’s water to its original state.

Like nitrifying bacteria, live plants also thrive on nutrients and pull them from the cloudy water microbes, eliminating them in the process. Moreover, they are also a constant source of oxygen during the day. This breaks down leftover fish food, fish waste, and microbes, killing them faster. As a consequence, the water starts clearing up.

Moreover, live plants are also effective in reducing ammonia levels caused by fish food and waste. Therefore, placing them in a new aquarium keeps the ammonia levels down. This also neutralizes cloudy water microbes, at least until the nitrifying bacteria are replicated.

How to Prevent Growth of Cloudy Water Bacteria

As mentioned above, preventing the growth of microbes is more critical than eliminating them once they have clouded the water. Therefore, when you have a new aquarium, make sure to add a small number of fish initially. Also, adjust the amount of food they’re eating by checking how much food they eat at one time.

Moreover, don’t clean the filter or replace its cartridge when you have a new aquarium. Again, this will do nothing except hinder the growth of nitrifying bacteria, which are actually beneficial.

If you think your filter is getting dirty too soon, you are feeding your fish too much, or you have too many in the same tank.

Also, don’t change the water too often, as it will only provide the microbes with more nutrients to feast on.


In a nutshell, when the water inside your fish tank gets cloudy, don’t be alarmed and start changing the water. Instead, leave the aquarium for a few days and see if there is any improvement.

Chances are that the water will clear on its own. However, you can add live plants and get the ammonia and nitrate levels tested if it doesn’t. This will give you an idea if any other problems are causing the cloudiness. These are steps you can take to achieve clean water and a healthy environment for your fish.