Aquarium Plants and Carbon Dioxide- Everything You Need to Know

One of the most popular questions aquarists ask is- can aquarium plants grow without carbon dioxide? Is it really an investment one should make to maintain the health of aquarium plants? In this article, we will learn the role of CO2 in the life of aquarium plants to help you understand whether this gas is a necessity or not.

Out of so many prerequisites for maintaining a healthy ecosystem inside an aquarium, one is carbon dioxide. It is the area where many beginner aquarists lack as they do not know the basics of carbon dioxide and its importance in keeping aquarium plants healthy.

The quick answer to it is, carbon dioxide helps certain aquarium plants abundantly. For others, it may not be a necessity but having CO2 will not harm the plants in water. So, whether you need carbon dioxide or not largely depends on the plant in question.

Keep reading to know why carbon dioxide is one of the requirements for certain aquarium plants growth and what are those plants that do not require carbon dioxide at all while growing in a low-tech planted tank.

Carbon Dioxide for Aquarium Plants- Is it a Necessity?

Carbon dioxide is essential for plants to perform photosynthesis, a process in which sunlight is used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds. In the absence of carbon dioxide, plants fail to perform photosynthesis which hinders their growth and may lead to death.

How much carbon dioxide will be needed depends upon the plant in question. While some plants require more carbon dioxide, others flourish in less.

So, whether it’s a terrestrial plant or aquatic, carbon dioxide is essential for plants’ proper growth.

When it comes to terrestrial plants, there is abundant carbon dioxide in the Earth that they utilize to perform photosynthesis. Such plants mostly attain carbon dioxide from the dead and decaying plant matter and substrate.

However, when it comes to aquatic plants, especially those inside an aquarium, the supply of carbon dioxide is much less. This is mainly because we keep on cleaning our tanks, leaving limited debris or degraded plant material that may decay and produce carbon dioxide that plants may use. Likewise, the presence of CO2 in tap water is also limited.

Verdict: Carbon dioxide is essential to perform photosynthesis which is the only way plants produce their food. So, it is a must for aquarium plants as well. However, some plants require more carbon dioxide to thrive, others perform well in low levels.

Since the scope natural carbon dioxide in aquariums is less, sometimes it becomes essential to induce additional carbon dioxide, especially, if the tank has aquarium plants with high carbon dioxide requirement. For others, it is not necessary.

 

Is there any way to escape using additional carbon dioxide in the tank?

Luckily, yes. One can take certain measures while setting their tank to ensure no additional carbon dioxide supplementation is required. Firstly, there are certain aquarium plants that do not require much carbon dioxide and can flourish even in low supply, secondly, being mindful while selecting aquarium plants and substrate and using some hardscape can increase the carbon dioxide level in the water.

Below are the tips that you need to keep in mind while setting your tank to ensure proper level of carbon dioxide maintains.

 

1. Plant Selection

One of the most important steps while setting up a new tank (especially for the beginners) is selecting the right plants. It becomes more necessary when you do not want to use additional carbon dioxide injection for plants’ growth.

At the same time, it is important that you have plants with almost the same carbon dioxide requirement in your tank. Having some plants with low requirements and others with high requirements will not give the best result. Likewise, if you have selected plants with high carbon dioxide requirements, escaping additional carbon dioxide injection may lead to the plant’s death.

It is when the right plant selection becomes the first and the most important step.

 

2. Perform Hardscaping

Using all natural decorative materials in the aquarium is called hardscaping. The most common materials used for the purpose are driftwood and aquarium rocks.

Adding all-natural materials as a tank décor offers two benefits-

• makes the tank look naturally more aesthetic
• increases the carbon dioxide level of the tank naturally

Hardscaping techniques are highly recommended to maintain a healthy ecosystem in the tank. These decorative items are easy to use, don’t require any care, and create a pleasing landscape.

Once you have put some driftwood in the aquarium, tie some aquarium plants on and around it. With time, the fungal and bacterial decay of driftwood decorations in the tank starts producing carbon dioxide.

Here, you need to keep an eye on to ensure decaying is less; otherwise, an excess of carbon dioxide may be produced, which is not good for the aquarium’s ecosystem.

 

3. Use aquarium substrate wisely

When you want to escape using additional carbon dioxide injection, choose the aquarium substrate wisely. Here, high-quality aquarium soil does wonders and ensure that you don’t need carbon dioxide supplementation. So, choosing the right aquarium substrate becomes a critical step.

There are two benefits of using high-quality aquarium soil for the plants. These are-

• Plants get enough nutrients from the soil, which is essential for their survival.
• The plant matter decomposes organically in the aquarium soil and keeps releasing carbon dioxide in the long run.
• Aquarium soil also releases slow carbon dioxide into the tank.

 

Thus, using high-quality aquarium soil can assist in proper growth of aquarium plants in different ways. Often, aquarists who have plants with high carbon dioxide requirements go for aquarium soil to ensure their health.

 

4. Use a Shallow Tank

Using a fairly shallow and wide tank is one of the tips to ensure that plants are getting enough carbon dioxide for their growth and development. This is because the chances of gas exchange are higher between air and water when the tank is shallower, and water has more surface area.

Thus, it will increase the chances of carbon dioxide from the air to enter inside the tank, fulfilling the plant’s requirements. The aquarium plants will easily feed on the carbon dioxide present above the aquarium water, especially if they grow tall and end up growing above the surface.

 

5. Restrict the amount of light

Light is one of the necessities of photosynthesis. Therefore, when you limit the access of the light to the aquarium plants, they do not get the chance to perform photosynthesis rapidly. However, in such conditions, plants grow at a very low pace.

So, if you don’t mind them growing slow, restricting the light will help coping up with low carbon dioxide in the tank.

On the contrary, when more light is available to the aquarium plants in the tank, they will perform more photosynthesis, utilizing all the available carbon dioxide.

Thus, when the plants have less light, they will use less carbon dioxide to complete photosynthesis. But, do not forget, when the plants perform less photosynthesis, their overall growth rate will also reduce.

 

Aquarium Plants That Don’t Require Additional CO2

As mentioned earlier, there are certain aquarium plants that require less carbon dioxide compared to others. Using such plants will be beneficial if you do not want to use additional carbon dioxide in the tank.

Below are some aquarium plants that require less carbon dioxide and can survive easily with their supplementation. Check them out!

1. Java Fern

One of the beginner-friendly plants, Java Fern is suitable for tanks with low carbon dioxide supply. Being a hardy plant, it can flourish perfectly in wide range of water parameters as well. At the same time, it doesn’t require additional carbon dioxide injection.

The best way you can use Java Fern is by tying it with driftwood or aquarium rock.

2. Cryptocoryne

Cryptocoryne is one of those aquarium plants that require a substrate to grow. In this case, you can use high-quality aquarium soil to plant it. While it doesn’t require a high level of carbon dioxide to survive, the little it will get from the aquarium soil will suffice.

At the same time, Cryptocoryne is an easy to care and maintain aquarium plant, making it beginner friendly. Another benefit is, it survives well in wide range of water conditions.

3. Anubias

Anubias is another easy to grow aquarium plant that beginners can try when they do not want to supplement aquarium with additional carbon dioxide. This plant can also thrive well in varying water conditions and require little care and maintenance.

4. Amazon Sword

Amazon Sword is one of those aquarium plants that bring greenery to the tank. The big, wide, and green leaves of this plant look great in all types of aquarium setups. At the same time, the carbon dioxide requirement of Amazon Sword is less than most of the other aquarium plants.

It can flourish in almost all conditions and substrates, making it a suitable beginner-friendly plant.

5. Vallisneria

If you are looking for an amazing, easy to grow and beginner-friendly background plant for your tank that require less carbon dioxide, Vallisneria is your go-to option. The long and green leaves of this plant grow tall, giving an aesthetic look to the tank.

Vallisneria can also grow in wide range of water parameters such as pH and temperature, leaving less chance for its failure.

Other aquarium plants with low carbon dioxide requirements-

 

1. Leptochilus Pteropus
2. Echinodorus grisebachii
3. Coontail
4. Hygrophila species
5. Limnobium laevigatum
6. Ludwigia repens
7. Duckweed
8. Rotala rotundifolia
9. Staurogyne repens
10. Mosses

These are some other aquarium plants that you can grow when you don’t want to supplement the tank with additional carbon dioxide. While some of these listed plants are beginner-friendly, others may have specific water requirements. So, research before selecting and choose wisely.

 Conclusion

Now that you know what is the role of carbon dioxide in a plant’s life and why it is one of the necessities, we hope you understand that it is something you can’t escape completely.

However, there is the possibility to grow aquarium plants without supplying them with additional CO2. Selecting plants with low CO2 requirement, and following certain tips while setting up the tank such as hardscaping, restricting light, using shallow tank and aquarium soil substrate are the key to maintaining healthy water ecosystem.