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How to Stop Cloudy Water in Fish Tank

how to stop cloudy water in fish tank

Having cloudy water in the fish tank is probably one of the most frustrating sights you can experience as an aquarium owner. It can be frustrating if you feel that you have already done a lot of maintenance to keep your aquarium clean and healthy, but the cloudy water keeps on showing in your fish tank. Meanwhile, having cloudy water on the fish tank can go back to you and your ability to maintain and keep the fish tank clean.

So, how to stop cloudy water in fish tank? How to deal with this situation if it’s always coming back? Most of the time, cloudy water indicates how healthy the water is for the fish. So it is essential to know the reasons behind the water being cloudy in your aquarium. We will also cover different ways that you can do to control, if not eliminate, the water from being cloudy in your fish tank. If you are frustrated right now, just read this article until the end to learn about stopping the water from being cloudy in your aquarium.


Why Does a Fish Tank Get Cloudy

There are many reasons why the fish tank is getting cloudy. But how did it happen, and what caused it to occur? It might be surprising to you, but there is no straightforward answer to the cause of this aquarium issue. The truth is, it could be driven by several factors which you should determine as a responsible aquarium owner. Most of these causes are easy to rectify as long as you are persistent in resolving the issue.

Not Fully Cycled

I have encountered new aquarium owners who just set up their fish tank,, but in just a few days, the water becomes cloudy already. Then, they changed the water and cleaned the filter media, thinking it might solve the issue, but the water was still cloudy. Why does it happen? Most often, when you are setting up a new aquarium, when the water does not fully cycle, the water gets cloudy when you start adding fish. But why is that? It is because of the bacteria that is suspended in the bottom, which makes the water cloudy.


Too much feeding of fish can also make the water cloudy in your aquarium. If you’ve put too much food in the aquarium and the fish will not eat everything, it will sink into the bottom of the tank and begin to rot. Then, all that food starts to dissolve and break apart then goes to the water.

Too Much Fish in a Small Tank

The water can also get cloudy if you own a smaller fish tank, but you put too much fish in it. If those fish interact with the sand or the gravel substrate, they can take a lot of stuff such as debris, food, and waste, creating cloudy water in the fish tank.

Inadequate Filtration

Filtration is an essential aspect of clean water maintenance, but if you fail to provide it in the aquarium, there is a big chance that the water will get cloudy. If your filter is not able to pull particular matters out of the water, then expect your water to be cloudy immediately. Also, if your filter is inadequate, meaning it’s too small for the amount of fish and the volume of water you are trying to filter, that can result in cloudy water.

Dead Fish

Another reason that makes the water cloudy is a dead fish. Sometimes, fish get stuck in woods or rocks and will die without you noticing it. This dead fish will start to decompose, which in turn makes the water becomes cloudy. The decomposing body of the fish can add additional organic materials to the water, which helps in turning the water into a cloudy state.

Dirty Glass

Lastly, this reason is often overlooked by most aquarium owners. Your fish tank can look pretty dirty, and the water may look cloudy, but it turns out that the glass is the dirty one. The bacteria in the water can produce a bioflim over the glass, which gives the fish tank a cloudy appearance. Sometimes, all you need to do is wipe the glass with an algae scraper and make a world of difference when it comes to the view quality of the glass.

Stopping Cloudy Water in Fish Tank

why does my fish tank keep getting cloudy

There are things that you can do to stop the fish tank water from being cloudy. Find out below:

Proper Fish Tank Maintenance

Doing proper maintenance of your fish tank can go a long way in preventing the water from being cloudy. What does it mean? One is to do a regular water change. The water change should be primarily based on the amount of nitrates on your fish tank. The amount of nitrates will determine how much and how often you change the fish tank’s water. You can also gravel vacuum the water tank if you are doing water change to remove all the debris, dirt, fish waste, and foods that are stuck in the bottom.

Glass Should be Clean Always

Make sure that you always keep your glass clean to make the fish tank appear a lot cleaner.

Proper Filter Maintenance

Having the right size of filter, the right type of filter media, and ensuring that the media gets saturated with fish waste, uneaten foods, and whatever else is floating to your tank is essential in keeping the water clear.

Make Your Water Fully Cycle

If you are starting a new tank, make sure that the water is fully cycled, or else it is expected that you will get a cloudy water because of the bacterial bloom. However, you can reduce the amount of food you feed to the fish to address this issue. The second thing, do not any more fish because adding some more will make the aquarium saturated with more fish waste and uneaten food, which will accumulate at the bottom. All of this stuff are food for the bacteria, which makes it bloom.

Another thing that you need to look for is the ammonia content of your aquarium. This chemical is very toxic to fish, and you should deal with it immediately. You can also install a used filter media coming from a reliable source or a clean fish tank and put it in the filter to help prevent ammonia or nitrates spikes later.


Learning how to stop cloudy water in fish tank is an essential skill for the overall maintenance of your aquarium. One way or the other, you will be going to face this problem shortly. What you do is know how to find the reason behind the cloudy water and make sure to do the right thing in looking for solutions that will make the water clear again.

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