Are Your Aquarium Plants Dying? Here’s what to do.

I can understand, it is is very frustrating when you see your beautiful aquarium plants dying.

Worst, you don’t even know why your aquarium plants are dying.

No worries…

In this blog post, I am going to share with you different reasons that may be causing this issue.

I will share the information by taking different scenarios so that it will be more helpful for you to know the exact reason or reasons and solutions to fix the problem.

Are Your Aquarium Plants Dying? Here’s what to do image

Aquarium plants are dying after planting it in the tank and what to do about it

There are several reasons that can cause your aquarium plants to die when they are planted in your aquarium.

Usually, the environment in which your aquarium plants are kept before you introduce them into your aquarium is different from the environment of your aquarium.

So the plants have to adjust to a new environment.

So there is an adjustment period for the plant.

During this period the plant may seem like they are dying.

But you just have to give them some time that could be between 3 days to up to 3 weeks to adjust them in your aquarium.

So be patient for 3 weeks. 

After 3 weeks, still, the problem persists then you can do the following things to fix the problem.

If the plant in your aquarium is dying then chances are it is not getting sufficient light for its proper growth.

So you should find out how much light your particular plant requires and then provide it with that lighting conditions.

Generally,  if you provide at least three watts of light per gallon, most of the plants will do fine.

Initially, when you plant some aquarium plant in your aquarium like Amazon sword which is a heavy root feeder.

You have to supplement it with fertilizers in the form of root tabs so that it can form a strong base in the substrate of your aquarium.

So when you introduce new plants in your aquarium you should supplement them with some fertilizers irregularly.

6 Tips to Take Care of Live Plants in Aquarium (For Beginners)

Aquarium plants are turning brown and then dying and what to do about it

If your aquarium plants are turning brown and dying then usually the reason behind it is high phosphate levels in your aquarium.

High nitrate levels can also cause the brown color of the leaves of the aquarium plants.

So in this case, the simplest way to reduce the phosphate or nitrate levels in your aquarium is to perform water change.

Also, you should regularly keep up with the weekly water change so that the problem will not occur again.

Aquarium plants are dying from bottom up and what to do about it

If your aquarium plants are dying from bottom up then usually low light is the reason behind it.

So if you are providing very low light to your plants say less than 1 watt per gallon then this is most likely the reason your aquarium plants are dying from bottom up.

How much light you should provide really depends on the particular species of the plant.

But usually, 3 watts per gallon light is sufficient for most of the plants.

At least they can survive under this lighting condition.

Besides, if you have any delicate species or demanding species of plant like Dwarf baby tears then in addition to the lighting requirement i.e. 3 Watts per gallon you will also have to supplement it with fertilizers and even carbon dioxide.

12 Benefits of Live Plants in an Aquarium (Pros and Cons)

Aquarium plant is dying due to algae growth

Extreme algae growth on the leaves of the aquarium plant can cause the death of the aquarium plant.

So if you notice a lot of algae on your aquarium plants, you will need to remove it from the leaves.

If the algae growth is very low then you can simply just rub off the algae from the leaves of your aquarium plant with your hands without even removing the plants from the aquarium.

If algae growth is moderate to high then you should remove plants from the aquarium and scrub it gently with a brush and then you should rinse them with clean water and put inside your aquarium.

In case you notice extreme algae growth on the leaves of your aquarium plants then you will have to go one step further to remove it from the leaves of your aquarium plant.

You have to actually bleach your aquarium plants.

Now in this process, your aquarium plants may get damaged and will not survive.

But when there is an extreme algae growth on aquarium plants, it is not going to survive anyway so it worth a try.

Aquarium plants are dying after water change and what to do about it

I assume there could be a couple of scenarios in this case.

The first one is, you have performed a regular weekly water change and without removing your plants from the aquarium and your plants are died after that.

The second scenario could be, you have removed the plant from the aquarium while performing the weekly water change and put it in another container filled with water.

So now let’s talk about the first scenario.

You should make sure that the temperature of the water you are putting in your aquarium is nearly the same as the temperature of the water in your aquarium. This is to maintain the temperature constant.

If there is a big difference in the temperature levels, it can not only shock your plants but also your fish.

And some delicate plants may not survive the shock and die.

Also, you should make sure that the water you are putting in your aquarium does not contain any harmful toxins like chlorine before introducing it into your aquarium.

In the second case scenario, you should make sure that the container in which you are putting your plants is not used with any chemicals.

Also, you should make sure that the water in the container has temperature the same or nearly the same as the temperature of your of the water of your aquarium.

Aquarium plants are dying even when you are supplementing them fertilizers and what to do about it

Fertilizes are very beneficial. They help to prevent many deficiencies in the plants.

But overdosing of fertilizers can also cause problems.

If you constantly keep overdosing your plants, it can even cause the death of the plants.

What is the sign of fertilizer overdose?

The good thing is plants don’t die immediately because of fertilizer overdose.

Plants show certain signs if you are overdosing it.

Brown spots

If you notice brown spots on the leaves of your plants then this could be the sign you are providing much more fertilizers than necessary to the plants.

These brown spots are caused due to brown algae growth.

It is caused because your aquarium contains much more nitrates than necessary to the plants.

How to lower the nitrates?

The simplest way to lower the nitrates is to do a partial water change. 

When you do a partial water change, the newly introduced water will dilute the nitrate in your aquarium.

Other reasons for brown spots

Besides fertilizer overdose, there are a couple of other reasons that can cause brown spots on the leaves of your aquarium plants.

Low light– If your plant is not getting sufficient light then it can cause brown spots on its leaves.

The thing is, the light requirements for every plant are different. 

Some plants like Java moss, Bacopa caroliana, Asian ambulia can grow in very low light but there are some plants like Lace plant, Amazon sword that does well in moderate to high lighting conditions.

So you should find out the light requirements of your particular plant and adjust the lighting accordingly.

Chlorine– Chlorine can also cause brown spots on aquarium plants. Besides, chlorine is harmful to the fish as well.

The mistake most beginners make while doing a weekly water change is introducing tap water without dechlorinating it.

So your aquarium water should not contain chlorine.

Check out our recommended Dechlorinating Agent

How to remove chlorine from the aquarium water?

There are a couple of ways to remove chlorine from aquarium water.

Use de-chlorinator– The simplest way is to use a de-chlorinator. 

Just add a few drops of the solution (as per the instructions mentioned on the label) in the water and that’s it.

Now-a-days ammonia is also used with chlorine to make tap water suitable for drinking.

So if you are using tap water for your aquarium then you should use a two in one dechlorinating agent that removes chlorine and ammonia from the water.

Use RO filtration– Another way to remove chlorine from the water is to filter the water through RO filtration system. 

Common deficiencies that can cause the death of the plants

There are several deficiencies that can cripple the growth, worse, it can even cause the death of your aquarium plants.

Carbon dioxide deficiency

Plants need CO2 just as we require oxygen. CO2 deficiency can cripple the growth of aquarium plants.

The symptoms of CO2 deficiency is crippled growth of the plant and yellow leaves.

To cope with CO2 deficiency, you should supplement the plants with CO2 fertilizers.

Also, you should regularly check the CO2 levels in the aquarium.

Nitrogen deficiency

Nitrogen is one of the important macronutrients for the proper growth of aquarium plants.

Aquarium plants take nitrogen in various forms such as urea, ammonium, and nitrate.

The symptom of nitrogen deficiency is the yellowing of the leaves of the plants, new leaves are relatively small in size than the old leaves and also the overall growth of the plant is crippled.

Besides, you may see an increase in the algae growth like hair algae when there is nitrogen deficiency in the aquarium.

You can use water tests that basically measure the nitrite level in your aquarium which helps you understand the nitrogen level in your aquarium.

The ideal nitrite level for aquarium is about 10 to 25 mg / NO2.

In case of nitrogen deficiency, you can increase the nitrogen level in your aquarium by adding liquid fertilizers that are rich in nitrogen.

Phosphorus deficiency

The symptom of phosphorus deficiency is increased in green spot algae, slow or crippled growth of plants and the shoot tips of the plant increases in size.

Phosphorus levels are measured in an aquarium by measuring the phosphate concentration in the aquarium.

The ideal phosphorus phosphate level for a planted tank is about 0.1 to 1 mg/l of PO 4.

Now, if you noticed symptoms of phosphorus deficiency in your aquarium plants then you can increase phosphate level by using phosphate fertilizers.

You have to be very careful while increasing this nutrient macronutrient in your aquarium because when you increase phosphate level in the aquarium, it will also affect the levels of other macronutrients in your aquarium.

For example, when you add phosphate fertilizers in your aquarium it will drop nitrite levels and even carbon dioxide level in your aquarium.

So you should measure other micronutrients level after adding phosphate fertilizers.

You should not add phosphate fertilizers frequently in your aquarium because plants are very good at storing phosphate.

So if you add phosphate fertilizers on a weekly basis then it can work just fine.

20 Tips to Maintain a Healthy Aquarium

Potassium deficiency

The common symptom of potassium deficiency is small pinholes on the leaves of the aquarium plant.

Besides, crippled growth of the overall plants and yellowing of the leaves are also symptoms of potassium deficiency.

You have to be careful while identifying the potassium deficiency because carbon dioxide deficiency can also cause pinholes on the leaves of the aquarium plants.

Also, magnesium deficiency shows similar symptoms as potassium deficiency.

So while identifying potassium deficiency, the first step is to measure the potassium level in your aquarium.

You can easily do so using any potassium water test.

The ideal potassium level for an aquarium is about 5 to 10 mg / l.

If you found potassium deficiency in your aquarium then you can easily up the level of potassium using potassium only fertilizers.

If there are multiple deficiencies like magnesium and potassium deficiency then you can use fertilizers that contain both the micronutrients.

Magnesium deficiency

Magnesium is a very important macronutrient for photosynthesis because it is a very important part of the pigment which is responsible for photosynthesis i.e. chlorophyll.

Plants don’t require a lot of magnesium but magnesium is often neglected altogether.

Usually, tap water contains magnesium so you don’t have to add magnesium separately if you just keep performing weekly water changes regularly.

But if your tap water doesn’t contain magnesium then you will have to add magnesium separately.

The symptom of magnesium deficiency in aquarium plants is the pale or yellow color of the leaves and the veins remain green.

Magnesium deficiency usually affects the old leaves of the plants first and later effects new leaves.

In case of magnesium deficiency, you should add fertilizers that contain magnesium and you will see improvements in a week or so.



When there is an iron deficiency in the plant, the plant is unable to form sufficient chlorophyll.

You can identify iron deficiency, especially in the fast growing plants from the leaves of the new shoots of the plants.

In case of iron deficiency, the leaves of the new shoots of the plant will turn pale.

In case of severe iron deficiency, there will be no chlorophyll in the leaves of the plant which will result in necrosis.

There will be black spots and holes on the leaves of the plants and its growth will be stunted.

When you notice iron deficiency, you should supplement the plant with iron only fertilizers.

The ideal iron level is 0.05 20.1 MG / l.

When you supplement plant with iron only fertilizers, it will rapidly consume it so after a couple of hours of adding iron fertilizers, if you test the water, you won’t even see any iron in the water.

Calcium, Boron and other trace elements deficiency

Calcium deficiency is very rare in aquarium plants because tap water contains calcium most of the time.

The symptoms of calcium deficiency are can be found in the new growth of the plant.

The new leaves of the plant will fade in color and they might even turn white. 

Also, their growth is stunted.

The ideal calcium level is about 20 to 30 mg / l.

Boron deficiency shows similar symptoms to that of calcium deficiency.

It is also a very rare deficiency.

If you supplement your plant with complete iron fertilizer then you don’t have to worry about boron deficiency because it contains Boron.

Other trace element deficiencies are very very rare and it almost never happens if you supplement your plants with fertilizers regularly.


Lighting is very important for the proper growth of aquarium plants.

Plants use lighting along with carbon dioxide and water for photosynthesis to make their own food.

So you should know and provide the amount of light your particular aquarium plants require and the kind of lighting your aquarium plants prefer.

The symptom that you are providing low lighting conditions to your aquarium plant is a very slow growth of your aquarium plants.

In the case of low lighting conditions, you can easily increase lighting by using supplemental lighting if you are not already using it.

You should also check if the plant is in the shading part of your aquarium.

Also, sometimes changing the placement of the plant can fix the issue.

For example, there are some plants like Hornwort that can be planted and can also grow without substrate i.e. you can keep them floating.

So in such a case, you can just remove it from the substrate and let it float, that way it will get more light.

How much light do aquarium plants actually need?

Generally, 8 to 12 hours of light is sufficient for the proper growth of aquarium plants.

Exactly how much light you should provide to your aquarium plants really depends on the particular plants in your aquarium.

Usually providing about 10 hours of light is a good starting point.

After providing 10 hours of light, if you notice a lot of algae growth then you should reduce the amount of lighting to 8 hours per day.

If you still notice your plants are growing slowly after providing 10 hours of light and there is no problem of algae growth then you can increase the lighting gradually to 11 and then 12 hours per day.

When you introduce a new plant in your aquarium then you should provide more lighting to the plants so that it can take root and grow fast in your aquarium.

But providing the ideal amount of lighting is not sufficient, you should also provide the ideal amount of lighting consistently.

And it is a very big issue among aquarists.

But thankfully there is a very simple solution to this problem. You can use lighting that comes with on and off timer or you can get a separate on and off timer and plug your lighting setup into it.

It will automatically start and stop lighting. This way, you can provide the ideal amount of lighting to your aquarium plants consistently.

The last thing to note is the lights not only provide light to your aquarium plants but it also produces heat in your aquarium.

Incandescent, VHO-fluorescent, and metal halide lights produce a lot of heat.

So you should avoid this kind of light in small aquariums because it can easily raise the temperature in your aquarium.

Also, if you are using these lights in your aquarium then you should regularly monitor the temperature of the water in your aquarium.

And in the case of high temperature, you can use these ways to lower the temperature.

Ideally, you should use standard fluorescent lights because it does not produce heat and it is suitable for most of the aquariums.


So as you can see there could be a lot of reasons that you are aquarium plants are dying.

Sometimes it could be multiple reasons and sometimes it could be only one reason.

So the key is to identify what actually causing the problem. And then applying the appropriate solution to fix the issue.

I hope you find this article helpful.

If you do, please share it on Pinterest.

Also, let me know if you have any doubts or suggestions in the comments section below.

Happy fishkeeping!

Photo of author
Prathmesh Gawai
He is the main author and editor at And he loves to share helpful information on aquarium and/or fishkeeping hobby. Prathmesh has over five years of aquarium and/or fishkeeping experience. Currently, he has a Betta fish tank. He has written hundreds of articles on various aquarium fish species and on fish tank maintenance over the last five years. Connect with him on YouTube here. Learn more about him here.

Leave a Comment