New Tank Cloudy Water No Fish: Cause and Solutions

Some queries that aquarists wonder: “What should they have to do to deal with a ‘new tank cloudy water no fish?’ What causes it? How to troubleshoot it?”

Fortunately, cloudy water in new aquariums is not certainly one emergency situation. There are several straightforward ways to treat cloudy water.

Keep reading to see more!

Cause and Solutions

cloudy water tank with no fish


If you find cloudy water in your aquarium after the first few days, worrying is unnecessary.

New set-up fish tanks can be considered blank biological slates. That means almost no life is present in them on the first day. Various microscopic organisms can start attempting to establish themselves within a few days.

As we all know, aquariums have beneficial bacteria that can filter the tank water and make balance and stability.

However, at this point, they don’t have an opportunity to appear in your system yet. Hence, it seems like a free-for-any for the first week or even more.

Many free-floating microbes and bacteria will use nutrients and minerals in your tank water and start to multiply uncontrollably, leading to cloudiness.

Sometimes, this situation will be aggravated and compounded when you add so many individuals at once or overfeed them, allowing these microbes to get an extra food source.


When you notice something is wrong with your aquarium, your first reaction might be to “do something,” requiring an action.

But taking methods to avoid and prevent the problem in advance would be better than trying to stop it when it happens. Once you notice cloudy water begin to appear in your new tank, it is wise to leave it running its course.

Keep reading to get some extra tips.

Avoid Putting Too Many Fish in Your Aquarium

More fish in your tank will lead to more leftovers and waste for the microbes leading to cloudy water. So many fish in your new tank may also lead to an increase in harmful nitrites and ammonia.

Avoid Overfeeding Your Fish

Inexperienced aquarists often worry their fish will starve to death, resulting in them overfeeding each day.

Unfortunately, there is little or no nitrifying bacteria to break down the uneaten food or resulting waste at this point, and the bad bacteria will use this to multiply.

In the worst case, harmful nitrite and ammonia levels may start to rise. Fish in nature do not always eat daily; some species may only eat once or twice per week. But no fish starves to death for three days.

Test the Tank Water

Check out the aquarium water for nitrite and ammonia as soon as your water gets cloudy. In most cases, the levels should be zero, meaning your aquarium has no problem.

Seed the Aquarium

If you have other well-established, healthy aquariums, adding gravel from this aquarium will seed the beneficial bacteria and boost the clearing process.

In fact, aquatic stores sometimes hold bio-sponges, wheels floating, and filter cartridges in stocked tanks to seed them with bacteria.

They might send those items home with your new tanks to nurture the biological balance. It should have the same result as putting gravel from one established aquarium.

Add Activated Carbon Media to Your Filter

Putting activated carbon pads or activated carbon media in your filter can help clear the tank water and remove nutrients that feed the cloudy water bacteria.


What Causes Green Water? 

“Green Water” outbreaks result from a sudden population explosion of suspended algae or phytoplankton.

Should I Don’t Anything and Leave Nature Taking Its Course?

Yes! You should do nothing in this case, as long as nitrite and ammonia levels do not rise. The bad bacteria will ultimately consume all the nutrients in your tank water and end up with the depth, which is part of a cycling process.

Changing the water for the aquarium helps to clean the tank water temporarily. After one or two days, the cloudiness will return, even poorer than before.

The reason is that the new water will provide a new nutrient supply, causing more cloudy water bacteria.

Is It Okay To Add Beneficial Bacteria Or Live Plants?

planted tank

Adding aquatic plants helps clean tank water

Yes! Aquatic plants hold “good” bacteria as well as other microbes, helping set the balance in your aquarium.

They will eliminate bacteria that generate cloudy water by competing for nutrients. Besides, they will produce oxygen, supporting the decomposition of uneaten food, fish waste, and cloudy water bacteria when they die.

They also absorb ammonia from uneaten food and fish, which can form in your newly set tanks till the nitrifying bacteria form.

Is It Okay To Replace Filter Media And Gain a New Filter?

The answer is No. The only thing you can do with your filter when the “cloudy water” problem happens is to avoid messing with it.

Replacing the media or cartridge or cleaning your new filter does not make sense and can remove any good bacteria that are attempting to establish.

Is It Okay To Change The Tank Water Often In This Case?

The answer is No. Regular water changes can be helpful in many cases involving aquariums, except for cloudy water issues.

Water changes can help clear your tank water temporarily. Yet, the cloudiness will return soon as you provide it with fresh water and a new nutrient source.


We know that witnessing cloudy water in your new tank can be worrying.

But we recommend being patient and giving it a while. Just stop adding any more fish, test your tank water, and leave your filter alone for the time being.

Cloudy water in one established aquarium is another problem. In this case, you should contact experts for timely advice.