Why Is My Fish Tank Cloudy? (Causes & Fixes)

All the fish owners know that a cloudy fish tank is annoying and distracting when trying to enjoy time with your fish. It is one of the most common issues faced by fish owners and can happen to any fish tank at any time. But why does this happen, and what leads to a cloudy aquarium?

Well, the answer isn’t straightforward because various factors drive the cloudiness of the aquarium; you just need to put a pin on your reason and then find its solution. The reasons are easy to rectify in most cases, but some may take a little more persistence to leave your tank alone.

So, to help you identify the issue with your tank, which is making it cloudy, we will write a brief guide you can refer to whenever you want to solve the cloudiness issue of your fish tank. So let’s get started. First, we will identify the reason and then look at the appropriate solution.

Why Is My Fish Tank Cloudy?

Is your new aquarium suddenly cloudy after being clear for a few days? Then don’t worry because a new tank can encounter these issues, and it is normal because it is like a clean slate, and there is basically no life present on day one.

But within days, the microorganisms will develop and try to establish themselves in the tank. For example, a beneficial bacteria that filters the water haven’t had a chance to create stability in a couple of days.

So some bacteria and microbes are free to float in the water and then start to multiply. Mainly the multiplication of microbes and bacteria is what causes the proliferation.

But, sometimes, the situation escalates when the fish owner adds a lot of fish to the aquarium or feeds them too much because those microbes get a chance of additional food sources.

Another reason why the water can get cloudy is the water that is used. If you use tap water, it can contain nitrates, silicates—heavy metals, or phosphates. So, if you are using tap water, try using a tap water conditioner to neutralize the elements in the water.

Here Are Seven Common Reasons Why You May Have A Cloudy Fish Tank

A cloudy fish tank is the most annoying thing ever. It makes the fish disappear and leaves only an ugly and appealing tank behind. However, if you face this issue, don’t panic because it is nothing that a little guidance and care can’t solve. 

There are 7 most common ways regarding how and why you might have a cloudy fish tank. So, read the list and think about which one suits your aquarium’s condition best.

#1- Filtration

Filtration is one of the major causes of a cloudy fish tank; especially if you have a mechanical filter, this has a higher chance of happening.

For example, if you have a power filter and a cheap one, it will use coarse foam through which the fine particles will pass. And if you have a canister filter, then the issue can lie in the foam you use.

However, a good option is to use good brands for filtration, which offer you foam densities; a more delicate foam is ideal for a more populated tank. Similarly, if using a power filter, then you can add an additional layer to your filter to improve the filtration

#2 – Don’t Overfeed

If you have a properly functional tank, then a common mistake on your part can be that you overfeed your fish out of love.

I know the fish look cute when you go near them with their tiny faces and small bubbles coming out of their mouths. But overfeeding is not the right way to show love because it doesn’t just pollute your tank but also makes the fish sick.

If you suspect that overfeeding your fish might be the issue, try laying off feeding them for a while to check and inspect the tank’s condition.

Then, don’t worry because most fish can live without food for one day. But, if the water stays cloudy for longer, then they can die. But, before you do this little experiment, consult your vet regarding how long your fish can live without water.

#3- Aquarium Plants

Many fish hobbyists like to keep plants in their aquariums, like bogwood and driftwood, which no doubt look fantastic in the aquarium but are also places for the growth of algae and microbes, which leads to being a food source for fry and fish. 

However, the plants can sometimes leach into the water and lower their pH, making it murky and cloudy. You can try removing the plants and then seeing whether or not the cloudiness will change.

#4- Clarifiers

A water clarifier is supposed to make your water clear and not cloudy. But, if you add too many clarifiers to the water, they will go on a clumping spree and turn your water cloudy.

The overdose of clarifiers isn’t harmful and can get out on its own in a few days, but it makes the aquarium unappealing.

If it happens once or twice, it will be harmless, but if it happens more frequently, it can also hurt your fish. That is why you should always measure the amount you have to add to the aquarium and then add it in. 

#5- Activated Carbon

Activated carbon is ideal for clearing the water and absorbing all the extra nutrients, which doesn’t help the fish to thrive, but instead allows the orgasms and bacteria to grow. It also kills the algae and takes away anything harmful and foreign from the aquarium’s water.

However, sometimes it happens that the dead algae, which the carbon is supposed to remove, detaches from the surface and starts to float in the water column. 

This issue can only be solved if you change the water and clean the tank regularly. You can also try to remove the activated carbon for a day or two to check the difference

#6- Inorganic Substances

All the inorganic substances in the aquarium, like gravel and artificial plants, are the hub of the growth of tiny organisms and excess nutrients.

When these inorganic substances aren’t appropriately cleaned from time to time, they can cause the whole aquarium to turn cloudy.

You can either clean the inorganic substances regularly or try to remove them altogether and then check the tank’s progress.

#7- New Tanks

One of the commonest reasons for cloudy water are new tanks. Since the tank is not introduced or set correctly, it is common to cycle a new tank, especially when you start adding livestock to the tank; it will be a new source of waste and nutrients.

If you add fish too much or too fast, then the whole system gets out of balance; the imbalance leads to the crazy production of nitrifying bacteria to digest the excess nutrients. This leads to your tank turning cloudy.

How To Fix A Cloudy Fish Tank?

Asking how you can fix a cloudy fish tank is one of the commonest questions that fish owners ask. How exactly can we clean and eliminate the milky white or brown water from the fish tank?

But the good thing is that cloudy water isn’t always an emergency situation, so you can quickly solve this issue. That is why we bring you some solutions to help you get rid of the cloudy waters.

Clean Cloudy Aquarium Walls

Your aquarium walls and glass can make your water tank look cloudy; the main reason for this is the bacterial biofilm; biofilm is the most obvious on driftwood, but it is not that obvious on the aquarium walls.

The biofilm makes the glass look as if it’s tinted, and the water looks cloudy if you leave it unchecked. Acrylic and glass tanks show better clarity when regularly and properly cleaned. 

However, you should remember not to use any toxic chemicals or complex substances to clean the walls, as they can harm your fish.

Particles in Water

Specks in water are easily formed, which can cause cloudiness. The cloudiness is most probably caused by excess food, fish waste, other marine life, dust, debris, and substrate.

For example, tiny substrate particles may enter the aquarium while setting up a new aquarium or put plants in an old aquarium and float around.

You should regularly clean those particles with a super fine fish net so that the water stays clean before it is time to change the water and clean everything. This way, the aquarium will always look clean, and the cloudiness will disappear.

Seed With Good Bacteria

By seeding, we mean that you should introduce items that can help the growth of good bacteria in the tank. That good bacteria can keep the atmosphere and water of the tank clean.

So, if you have a well-established tank, take a handful of gravel from that aquarium and add it to the aquarium with cloudy water. Or you can add plants which will also help speed up the good bacteria process.

Apart from this, you can also add aquatic stones or filter cartridges, wheels floating or bio-sponges, etc.; all this will make the biological balance go into full swing.

Make Regular Water Changes 

Proper and regular maintenance is the easiest and quickest way to solve the cloudy water issue of the tank. Frequent water changes can help you in restoring the balance of the aquarium. The bacteria bloom due to leaving unchanged water for too long in the water. 

If you change the water regularly (not every day), you will see that your issue will be solved 50% of the time. However, if the problem is severe and the cloudy water doesn’t leave your water tank alone, then you can try vacuuming the gravel to remove the top layers of residue.

Keep Up With Regular Filter Maintenance

If you ignore the maintenance of your aquarium’s filter, there is a big chance that your tank water can turn cloudy.

Mostly when our mechanical filter has too much residue on the filter and it isn’t working to its fullest, then you should either replace the filter floss or clean the sponges. Try to change the filter floss every week so that the water stays clean and healthy for your fish. 

You should basically clean out all the components of the filter, from the piping to the tubing and sponges of your filter; everything should be cleaned or replaced after every few days. All the maintenance pays off when your fish stays happy and healthy.

Improve The Quality Of Light And Reduce Lighting Times

Poor and dull lighting takes all the charm out of the aquarium and makes everything look cloudy and hazy. This issue more commonly happens with LED lights because these lights are more focused than T5 lighting.

Unfortunately, concentrated lights can lead your aquarium to look gloomy and shadowy. To fix this problem, you can use LED fixtures that can expand the light to even the deepest corners of the tank.

On the other hand, if you have T5 lights, then you should replace them so that your aquarium may look bright and happy because these lights make the display clearer and more lively.

So, maybe your cloudy water issue is because of your dull or old lighting. Besides, reducing your lighting timing can also help reduce cloudy water because the algae will grow less, and the glass will stay clean.

Proper Fish Tank Maintenance

Fish tank maintenance is the key solution to keeping your tank water from turning cloudy, no matter the reason.

Overfed the fish and have waste in the water, glass is dirty, lights are dull, the filter is clogged, water is cloudy, or clarifiers aren’t doing their job? Everything can be solved with the maintenance of the aquarium.

Maintenance isn’t just about changing the water regularly; it is also about keeping everything in your aquarium balanced. Regular maintenance can solve about 80% of your aquarium issues. But if the problem gets more serious, then you can consult your vet.

How Long Does It Take For A Cloudy Water Tank To Be Fixed?

The time required for cloudy water to be fixed depends on the fish owner. If you are able to identify the issue and get right on solving it, then your cloudy water issue can be solved in a couple of days.

However, sometimes, even after the issue is identified, it takes a few weeks for the balance of the aquarium to be restored, and with time you will see a positive change in the atmosphere of your tank.

Cloudy water is not highly hazardous for your fish, and it can take some time to solve the issue, but during all that time, you need to stay persistent and keep trying to solve it. Then, you can try the different things we mentioned to see if they work for you.

More guides:

• 20 interesting & exciting fish tank ideas in 2023
• How to lower nitrates in the fish tank? (know all)
• How to lower ph in an aquarium? (safely & easily)
• How to plant aquarium plants? (the right way!)
• How to dispose of aquarium water (maintain quality)