Does Aquarium Need CO2? – verywellFishing

When I first became interested in aquarium I looked for various important information about aquarium. Of course I’m also looking for information about CO2 and whether an aquarium must use CO2 to be successful. After I searched I finally found the information.

Does the aquarium need CO2?

The short answer is it is necessary. Just like plants on land, plants in water also combine light, CO2, and other nutrients to photosynthesize in order to grow.

After getting this answer, don’t rush to cancel your intention to make an aquarium or directly buy CO2 equipment which is certainly not cheap. In this article, I will explain some important things about CO2 so that you don’t get the wrong idea about aquarium that must use CO2. Due to the fact that not all aquarium require CO2 to help plant growth.

The main reason for adding CO2

So now you know that aquarium plants or aquatic plants are the same as plants on land and require CO2 to grow. But you also need to know that without you adding CO2, there is already CO2 content in the aquarium. This CO2 comes from various things such as fish breathing, the decay of plants and the circulation of water produced by pumps or filters. So without you adding CO2, actually there is already CO2 in the aquarium, only the CO2 level is not too much so that for most plants it will not be enough to support growth.

The main reason for adding CO2 to an aquarium is to accelerate plant growth because there are some plants that need a lot of CO2 to grow well. For example, you want to grow carpet plants so that the front view of your aquarium becomes more beautiful. Carpet plants usually require CO2 to grow quickly and well, for example, Hemianthus callitriodes ‘cuba’ ( HC/dwarf baby tears ), Glossostigma elatinoides , Eleocharis acicularis ( Dwarf hair grass ).

Of course there will be consequences if you want to add CO2 to your aquarium. Because there is a lot of CO2 content in the aquarium after you add CO2, it doesn’t mean your plants will grow quickly just like that. You also have to compensate with sufficient light from your lamp. Because if there is not enough light, even though there is enough CO2, plants cannot photosynthesize quickly.

So the first thing you should consider before adding CO2 or even before making an aquarium is what plants you will use. Because this type of plant will affect all components of the aquarium. If you really want to add a lot of plants that require a lot of CO2, then you really need to add CO2 and also enough light because usually these two things are directly proportional.

If you are going to use plants that don’t really need CO2 then you can save money and not buy CO2 equipment. But that doesn’t mean you can’t add CO2 if you use plants that don’t really need a lot of CO2. All plants will be happy if there is a lot of CO2 content, but there are some plants that are more resistant and can grow even with less CO2.

So before you make an aquarium and buy a lot of plants, you should decide what plants to choose. We recommend collecting plants that have the same CO2 needs. If you are going to make a low-tech aquarium, you should use plants that don’t require a lot of CO2 intake. But if you really want to make a high-tech aquarium, you are of course free to choose any plant because everything will grow well with a lot of CO2 and light intake.

Plants that do not require CO2

I briefly discussed earlier that most carpet plants require CO2 and sufficient light to grow well and quickly. Of course, not all aquasacpe plants require difficult maintenance. I will give some examples of plants that you can use if you want to create a low-tech aquarium.


Anubias is the easiest plant in my opinion to grow and is perfect for beginners who are going to make their first aquarium. Anubias can live even though it only gets a little light and CO2. Not only that, you also don’t need soil or basic fertilizer because Anubias doesn’t need it. You just have to tie it to wood or stone.

Java Fern

Just like anubias, java fern does not require soil or basic fertilizer because it can live by simply binding it to stone or wood. Java ferns are also very easy to maintain and do not require a lot of CO2 and light. You need to know that this anubias and java fern do have roots, but they should not be planted because they will rot. Plants such as anubias and java fern obtain nutrients by taking them from water instead of soil.


I will summarize the long explanation earlier at this conclusion so those of you who don’t want to read too much can find the answer here. Does the aquarium need CO2? The answer is necessary and depends on what plants will be used. If you use carpet plants such as Hemianthus callitriodes ‘cuba’ ( HC/dwarf baby tears ), Glossostigma elatinoides , Eleocharis acicularis ( Dwarf hair grass ) you should not only use CO2 but also light and sufficient basic fertilizer to grow fast and well.