Why Is My Aquarium Water Yellow?

Why Is My Aquarium Water Yellow

Looking at the colorful fish swimming around in a beautiful aquarium has a calming effect on nerves.

After a long day, being around an aquarium and looking after your fish can help you unwind.

Everyone likes to watch fish swim around peacefully in the tank – blowing bubbles and hiding behind aquarium decorations.

However, one thing that can be severely off-putting about an otherwise stunning aquarium is yellow tank water.

Yellow aquarium water diminishes the overall aesthetic appeal of the aquarium. It makes it hard for you to look at the fish and care for it.

Sometimes, it can even be harmful to the health of the fish or your aquarium plants. It makes your tank look dirty and unkempt.

The worst part is that the water in your aquarium can turn yellow even with proper plumping and filtration.

For all these reasons, it is essential to identify the reasons behind yellow aquarium water and take steps to ensure that the water in your aquarium always remains clean and clear.

So, what can you do to keep your aquarium water from yellow? How can you make sure that it is always clear and never diminish the aesthetic appeal of your tank?

Read on to find out the most common causes of yellow aquarium water and learn what you can do to tackle the problem!

What Causes Aquarium Water to Turn Yellow/Murky?

The water in your tank can turn yellow or brown for many reasons.

It is for you to figure out what’s causing the problem and take suitable steps to fix it.

Bacteria Growth

Bacteria growth is the most common culprit behind murky water. As you may already know, your aquarium is full of bacteria.

Some of it is healthy and even essential to keep your fish happy and healthy.

However, unnatural growth of bacteria can cause multiple problems in the tank and yellow water is one of them.

Bacteria overgrowth is commonly known as bacterial bloom or blossom.

When you are dealing with bacteria overgrowth, the water in the tank is more likely to turn gray or cloudy rather than yellow or green.

This is the giveaway sign of bacteria blossom. In other words, if the water is tinted, you can narrow down the causes by ruling out the possibility of bacteria growth.

Organic Compounds

Sometimes invisible to the naked eye, organic compounds are almost always floating around in the water tank.

These include uneaten food particles, waste produced by fish, and dead or decaying parts of aquarium plants.

Over time, these organic compounds easily get dissolved in the water. After a while, they break down and change the chemistry inside the tank.

As a result, you may notice a green or yellow tint in the aquarium water. The water may also turn cloudy and murky.

Keep in mind that dissolved organic compounds are very harmful to the health of the fish.

Apart from that, these particles can also ruin the overall aesthetic appeal of your tank, giving it an unkempt look. Furthermore, they can also lead to unpleasant odors that are generally off-putting.

Therefore, it is important to take care of this problem without wasting any time.

As soon as you spot tinted water or an unpleasant smell rising from the tank, take steps to fix this problem.

Driftwood Tannins

Certain kinds of wood, especially driftwood and bogwood, can lead to water discoloration.

The reason is tannins. These woods contain tannins which are released into the tank water over time.

Tannins have a yellow tint and turn the water yellow. Keep in mind that since tannins are acidic in nature, they will also disrupt the pH level in the aquarium.

In other words, yellow water and lower pH levels are telltale signs of the presence of tannins in the tank.

Water discoloration due to tannins in the water should not be troubling as long as you have fish that can strive at a lower pH level.

Therefore, make sure you learn about the pH preferences of your fish if the water unexpectedly turns yellow or when you introduce new fish in the aquarium.

Other than that, yellow water due to tannins should not be a problem.

And the best part is that the discoloration caused by tannins generally goes away on its own as the level of tannins depletes in the water.

You may be surprised to know that some kinds of fish even like the slightly yellow tint caused by tannins as it is closer to their natural habitat.

Unwashed Substrate

It is quite common to notice cloudy or tinted water after adding a new substrate in the aquarium water.

Irrespective of the type of substrate that you choose for your aquarium, it is likely to be covered with dust particles.

Once you introduce this substrate in the tank, these dust particles dislodge from the substrate and swim around in the tank.

This causes discoloration in the aquarium water and turns it cloudy.

So, if you notice discoloration right after adding substrate, know that the culprit lies at the bottom of the tank!

Related Article: How to Clean Aquarium Sand?

Lighting Period

This is another important factor that may lead to cloudy, discolored water.

While the lighting period that you have set for your tank may not affect the water directly, it can act as a catalyst for bacteria production.

This can lead to a fully-fledged bacteria bloom in your tank.

As discussed above, the overgrowth of bacteria will then affect the clarity of the water in the aquarium.

What to Do About Aquarium Water Turning Yellow

Now that you know what may cause the aquarium water to turn yellow, the only question remaining is what you can do about it.

The first thing that you need to do is identify the root cause of water discoloration in your tank.

Only then you will be able to solve this problem once and for all. Let’s take a look at some tried and tested tips that can help you deal with tinted water.

Determine the pH Level of the Water

If tannins are the problem, the pH level of the water will drop.

You can easily check it by conducting a pH test. The easiest way to deal with this problem is to get rid of driftwood or bogwood decorations.

Replace them with something more suitable for your fish.

However, if the fish don’t mind a lower pH level, you don’t need to do anything. Keep your décor, sit back, and simply wait for the discoloration to go away on its own.

Determine Ammonia, Nitrite, and Nitrate levels

If you find that ammonia, nitrite, or nitrate levels are high in the water, you are probably dealing with bacteria overgrowth. Keep in mind that this can be toxic to your fish.

Therefore, take action immediately and replace the water. A 50% water change may do the trick as it will decrease the level of toxins in the water to half.

Don’t forget to re-test the level of ammonia, nitrite, and nitrate after replacing the water.

Keep the Lights Off

Extended periods of lighting in the aquarium can sometimes promote bacteria and algae growth.

Keeping the lights off may do the trick and help you control the bacteria bloom which may be causing water discoloration in the tank.

Related Article: How Long To Leave Aquarium Lights on In a Planted Tank?

Cleaning the Aquarium

A clean tank is a healthy tank. One of the most common reasons for discolored or cloudy water is unclean tanks. Is there debris floating around in the tank?

When was the last time you wiped the walls of the aquarium from the inside?

Do you clean the aquarium substrate properly? It is essential to ask yourself all these questions as negligence when it comes to tank cleanliness is out of the question if you want to keep your fish happy and healthy.

Check the Filter

A filter may clog without you noticing.

It may still work but its performance will take a hit. Therefore, if the water in your tank is regularly turning murky, check your filter for faults or damage.

If you find any problem, fix it immediately.

Should You Worry If Aquarium Water Turns Yellow?

Don’t panic at the first sight of tinted yellow water!

It is important to understand that it is common for water to occasionally turn cloudy or yellow in an aquarium.

So, don’t drain your tank every time the water becomes a little unclear as it can stress out your fish.

For instance, if cleaning is due and you notice murky water in the aquarium, there’s probably nothing to worry about.

However, noticing an unexpected yellow or brown tint in the water can be a sign of trouble. If that happens, make sure you investigate the root problem instead of simply draining the aquarium.

This is important as it could be something that may have adverse effects on the health of your fish.

Now that you know what causes discoloration in the aquarium water and what you can do about it, you will never have to worry about dealing with yellow aquarium water again.

Your tank can now look its best you can also keep your fish happy and healthy without much hassle!

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