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29 Easy-Going Aquarium Plants That Don’t Need CO2 Injections

29 Easy-Going Aquarium Plants That Don’t Need CO2 Injections

If you’re just starting to deal with aquascaping, you might feel overwhelmed with all the new care requirements you need to think of. Fertilization, soil type, injections… Fortunately, with aquarium plants that don’t need CO2, you’ll have one less thing to think about!

All plants need CO2 for growth and respiration. It is a byproduct of fish respiration, meaning you can find it naturally in your tank. However, this amount isn’t enough for some plants and they require additional carbon dioxide.

Luckily for you, these are not such plants! 

All 29 plants I’ve listed can survive with the amount of CO2 naturally found in a tank with fish. While some might use extra CO2 for faster growth or to thrive, they don’t require it in order to live and reproduce.

Without further ado, here are some aquarium plants that don’t need CO2 supplementation:

1. Hornwort

hornwort plant

Hornwort is one of the easiest plants when it comes to caring. If it wasn’t so beautiful, I am certain many people would consider it a weed!

This bright green plant doesn’t need any additional carbon dioxide or fertilization. It can even grow floating, without any substrate whatsoever!

It can even produce tiny, white flowers without any special care or requirements. You can just forget about it and it will thrive! Truly an amazing plant.

Scientific name:Ceratophyllum demersum
Light requirement:Moderate
Growth rate:Fast
Maximum height:10 feet
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

2. Water Weed

elodea in aquarium

Water weed is, as its name suggests, considered a weed in many lakes and ponds. Still, many aquarists love adding it to their tanks due to its easy care and interesting, dark-green leaves. 

This plant grows rather fast even without any CO2 supplementation or plant food. This makes it stand out from most other plants on our list that require at least some CO2 injections in order to keep their growth rate.

This plant is so resistant it is one of the few aquatic plants that remains green all winter long! It can even survive in frozen lakes! 

While not invasive, there are many efforts to control the growth of this plant in nature. As such, I would suggest you compost it instead of throwing it out.

Scientific name:Elodea
Light requirement:Low to high
Growth rate:Fast
Maximum height:8 feet
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

3. Ludwigia

ludwigia repens plant

While there are many species of Ludwigia found at aquatic stores, the red-leaf ludwigia (ludwigia repens) is the most popular one, so I’ll talk about it here. 

This plant is known for its bright red color that makes it a centerpiece of every aquarium. It’s hard not to look at her gorgeous leaves!

While this plant requires no CO2 injections, you should provide it with lots of light and some fertilization. Otherwise, its red color might become dull and pale.

Scientific name:Ludwigia repens
Light requirement:Moderate to high
Growth rate:Fast
Maximum height:20 inches
Substrate requirements:Nutrient-rich substrate
Nutrition:Fertilization is advised
Care difficulty:Easy

4. Bucephalandra

bucephalandra plant in aquarium

Bucephalandra is a hardy plant that comes in several color varieties. However, most common types have dark green, brown, or even purple leaves!

This plant can grow in harsh conditions. It doesn’t require CO2 supplementation to thrive, but you might want to make sure it’s properly fertilized.

As it’s susceptible to algae, you need to ensure the plant is in good health. This also means not leaving your aquarium light on during the night – something that will benefit your fish, as well.

Scientific name:Bucephalandra
Light requirement:Low to high
Growth rate:Slow
Maximum height:10 inches
Substrate requirements:Sand, driftwood or rocks
Nutrition:Fertilization is advised
Care difficulty:Easy

5. Java Fern

java fern plant
Photo: ryowatanabee

There are many varieties of java fern out there, such as java fern trident, needle java fern, or Windelov java fern. One of the things all of them have in common is that they are rather resilient plants. 

Java fern doesn’t require any CO2 injections. It also doesn’t need any additional feeding. In general, this plant is capable of taking care of itself. It doesn’t even need any substrate to grow!

Due to its slow growth, you don’t even have to groom it. This truly is a beginner-friendly plant.

Scientific name:Microsorum pteropus
Light requirement:Low
Growth rate:Slow
Maximum height:15 inches
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

6. Java Moss

vesicularia dubyana plant
Photo: gonta_aqua

Java moss is one of the most popular aquarium plants that don’t need CO2. This is mostly due to its easy going nature. 

Just like java fern, java moss doesn’t require any substrate. However, it might grow a bit faster if you allow it to reside on a nutrient-rich substrate. Despite this, any type of soil will do. 

Be careful with fertilization! Certain minerals might affect the appearance of this plant. If there is too much (or too little) of any micronutrient, java moss will let you know. 

Still, if your tank has proper water condition and some fish in it, this plant shouldn’t need any additional feeding.

Scientific name:Vesicularia dubyana
Light requirement:Low to high
Growth rate:Fast
Maximum height:4 inches
Substrate requirements:Any substrate  
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

7. Anubias

anubias plant in aquarium

There are many reasons why anubias is as popular as it is. One of them is likely due to its easy maintenance and lack of any special requirements. The other one is probably as this is one of the few aquarium plants that flower underwater.

This plant has beautiful, thick leaves, doesn’t require any CO2 supplementation, it can live without fertilizers, and it won’t get eaten by herbivorous fish. What more could you want from a plant?!

Scientific name:Anubias barteri
Light requirement:Low
Growth rate:Slow
Maximum height:16 inches
Substrate requirements:Any type of substrate
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

8. Brazilian Pennywort

One of the two plants originating from Brazil that I’ll mention, Brazilian pennywort is a relaxed plant that can grow on almost any substrate. You can even grow it on rocks, together with a few other plants.

Brazilian pennywort doesn’t require almost any care at all, except for a bit of feeding. It can survive on CO2 produced by the surrounding fish, and it can survive in all light conditions – although mine seem to thrive on moderate light. 

While fast-growing, this isn’t a particularly large plant, so it probably won’t take over the whole of your tank even if you forget about it for a little while.

Scientific name:Hydrocotyle leucocephala
Light requirement:Moderate
Growth rate:Fast
Maximum height:8 inches
Substrate requirements:Any type of substrate
Nutrition:Requires fertilization
Care difficulty:Easy

9. Amazon Sword

Amazon sword is a plant that is very easy to recognize. Unless you’re entirely new to the hobby, chances are you’ve had an Amazon sword in your collection.

This plant doesn’t require anything except a bit of liquid fertilizer, but if you’d like it to grow fast and to thrive, CO2 injections are recommended. Still, it can do just fine in an aquarium with lots of fish, so you don’t have to worry about supplementation.

Unfortunately, amazon swords are a tasty snack for your oscars, tiger barbs, and goldfish. Be careful what fish you pair them with.

Scientific name:Echinodorus grisebachii
Light requirement:Moderate
Growth rate:Moderate
Maximum height:20 inches
Substrate requirements:Nutrient-rich substrate
Nutrition:Fertilization is required
Care difficulty:Easy

10. Water Lettuce

brazilian pennywort

Water lettuce is a floating aquarium plant that looks just like – you’ve guessed it! – lettuce. Although in most tanks it won’t grow as much to be the size of a real lettuce or cabbage. Its long, hanging roots can be a nuisance, but most fish love swimming between them.

This plant requires some care. For example, you should feed it with liquid fertilizer with each water change. Also, while it can survive without additional CO2, you might consider supplementing it a bit, just to make sure it thrives.

While water lettuce isn’t edible the same way as regular lettuce, it does have some medical properties.

Scientific name:Pistia stratiotes
Light requirement:High
Growth rate:Fast
Maximum height:10 inches
Substrate requirements:None
Nutrition:Requires fertilization
Care difficulty:Moderate

11. Vallisneria

vallisneria plant in aquarium

There are many types of vallisneria plants, but all are easy to care for. They are rather adaptable and don’t require any challenging maintenance tricks. 

This plant doesn’t require CO2 injections, but if you don’t have too many fish in the tank, you might want to supplement it from time to time to ensure fast growth. Fertilization is necessary, as vallisneria requires lots of energy.

Just like with a few other plants I’ve listed, you shouldn’t keep vallisneria with fish that love to eat plants. Even though it has a fast growth rate, herbivores consider it to be a tasty meal, so it might end up ruined in no time.

Scientific name:Vallisneria
Light requirement:Moderate
Growth rate:Fast
Maximum height:20 inches
Substrate requirements:Sand
Nutrition:Requires fertilization
Care difficulty:Easy

12. Water Spangles

salvinia minima

Water spangles is another fast growing plant that can thrive with minimal care. It can survive in most light conditions, doesn’t require CO2 supplementation, and doesn’t need fertilization.

This floating plant is often confused with duckweed, but its leaves are significantly larger, although still small. They grow in joint sets of three, with one leaf remaining underwater. 

Water spangles are considered invasive, as they can quickly grow over entire ponds and swamps. 

Scientific name:Salvinia minima
Light requirement:Moderate to high
Growth rate:Fast
Maximum height:4 inches
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:Moderate

13. Red Tiger Lotus

Red tiger lotus is a fairly large floating plant suitable for big aquariums. It has gorgeous, red leaves and dreamy white flowers.

While it might seem that a plant with such a unique appearance is challenging to keep, its care is actually pretty straightforward. It doesn’t require any CO2, can live in various water parameters, and it only needs a bit of feeding to grow properly.

Due to its side, I would advise you to regularly prune your red tiger lotus. Otherwise, it might grow too big for most aquariums.

Scientific name:Nymphaea zenkeri
Light requirement:Moderate to high
Growth rate:Moderate
Maximum height:35 inches
Substrate requirements:None
Nutrition:Fertilization is advised
Care difficulty:Easy

14. Moneywort

bacopa monnieri

Also known as waterhyssop, moneywort is easy to recognize due to its thick stems and small, round leaves. It might look like a long succulent growing in your tank. 

This is yet another easy-going plant that only needs the smallest amount of care to survive. While you might want to fertilize it to give it more energy for its fast growth rate, it generally doesn’t require any feeding or CO2 injections.

Just like water lettuce, moneywort has numerous health benefits, which is why it’s often used not just for aquascaping but for medical purposes.

Scientific name:Bacopa monnieri
Light requirement:Low to medium
Growth rate:Slow
Maximum height:12 inches
Substrate requirements:None
Nutrition:Fertilization is advised
Care difficulty:Easy to moderate

15. Water Wisteria

hygrophila difformis or water wisteria

Even novice aquascapers have most likely heard of water wisteria, or have at least seen it in a pet store. This plant is effortless to keep, grows rather fast, and you can grow it in almost any pattern imaginable. 

Water wisteria doesn’t require any CO2 or fertilizers, and it can survive in most water parameters. However, nutrient deficiency can result in browning of its leaves, or it can even turn the plant white or pale

 As such, I would still advise you to monitor your micro- and macronutrient levels inside the tank to avoid possible issues.

Scientific name:Hygrophila difformis
Light requirement:Moderate to high
Growth rate:Fast
Maximum height:20 inches
Substrate requirements:Sand or gravel
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

16. Cryptocoryne

cryptocoryne wendtii plant aquarium
Photo: saadatalaa

Cryptocoryne is a non-demanding plant that comes in several shades and colors, such as green, brown, or red. It is recognized by its ruffled foliage that is similar to the ruffled sword plant.

This plant can grow without any additional CO2, but you might want to give it a bit of fertilizer every now and then – especially if you decide to grow it on rocks or driftwood. 

Cryptocoryne doesn’t deal well with sudden changes in the environment. When you first add it to your tank, it might appear as if it’s dying. Also, while it can live in various conditions, make sure to keep the parameters stable.

Scientific name:Cryptocoryne wendtii
Light requirement:Low to moderate
Growth rate:Slow
Maximum height:10 inches
Substrate requirements:Sand or gravel
Nutrition:Optional fertilization
Care difficulty:Easy

17. Marimo Moss Ball

Despite its name, marimo moss ball is not actually moss but rather a type of spherical algae. They originate from Japan and it might be a bit challenging to get your hands on them due to strict import laws. For example, there is a quarantine against the importation of marimo moss balls in Wyoming!

These little balls are effortless to grow, which is one of the reasons why so many aquarists want to get a hold on them. They require no feeding, no CO2, and no special water parameters. They can even survive inside a fridge!

Not just that, but they have extremely long lifespans. These algae can live for more than 200 years! No wonder why they are considered a nuisance in nature

Scientific name:Aegagropila linnaei
Light requirement:Low to medium
Growth rate:Slow
Maximum height:37 inches
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:Easy

18. Dwarf Sagittaria

sagittaria subulata
Photo: dcr.aquarium

Dwarf sagittaria is a grass-like plant that is usually used as an aquarium carpet. It spreads really fast and gives each tank a prairie appearance.

It doesn’t require any additional CO2, but due to its fast growth rate requires lots of fertilization. Also, it is somewhat picky about water conditions and can die if you make sudden changes. 

Still, I would give it a shot due to its beautiful appearance. Under certain light the leaves might have a reddish tint!

Scientific name:Sagittaria subulata
Light requirement:Moderate
Growth rate:Fast
Maximum height:20 inches
Substrate requirements:Nutrient-rich substrate
Nutrition:Requires fertilization
Care difficulty:Hard

19. Micro Sword

lilaeopsis brasiliensis
Photo: comipez

Micro sword looks similar to dwarf sagittaria, except it’s – like its name suggests – much smaller. It can make your tank look like you have a lawn in it!

While it doesn’t require any CO2 to survive, it will certainly benefit some supplementation, especially as this plant can be a bit tricky when it comes to choosing proper water parameters. 

Micro swords require lots of light, nutrient-rich soil, warm water, and neutral pH value. If any of the water parameters change, the plant can die. 

Due to its care requirements, this might not be the best plant for beginners. 

Scientific name:Lilaeopsis brasiliensis
Light requirement:High
Growth rate:Fast
Maximum height:4 inches
Substrate requirements:Nutrient-rich substrate
Nutrition:Requires fertilization
Care difficulty:Moderate

20. Whorled Pennywort

hydrocotyle verticillata

While there are many plants from the Hydrocotyle family that are easy to care for, whorled pennywort requires some additional effort, as it can only survive in fairly strict water parameters.

Still, it doesn’t require any CO2 supplementation and can survive without additional feeding, so you don’t have to think about that.

Whorled pennywort is among the small aquarium plants, so it doesn’t require any pruning or cutting. Also, it can grow both in water and out of it.

Scientific name:Hydrocotyle verticillata
Light requirement:Moderate
Growth rate:Moderate
Maximum height:3 inches
Substrate requirements:Any substrate will work
Nutrition:Fertilization is recommended
Care difficulty:Moderate

21. Brazilian Waterweed

egeria densa
Photo: gonta_aqua

Commonly known as anacharis, Brazilian waterweed is one of the more common aquarium plants. It grows rather quickly, doesn’t care too much about water parameters, and is mostly resistant to fish trying to nip on it. 

Since this plant doesn’t require any CO2 or fertilization, the only thing you need to think about is the amount of light the plant is getting. Too little light will stunt its growth, but too much light can cause discolorations.

If you decide to plant Brazilian waterweed in substrate instead of allowing it to float, make sure to avoid combining it with burrowing fish such as kribensis cichlid. Such animals can harm its delicate roots by accident.

Scientific name:Egeria densa
Light requirement:Moderate to high
Growth rate:Fast
Maximum height:8 inches
Substrate requirements:Any substrate
Nutrition:Advised fertilization
Care difficulty:Easy

22. Flame Moss

Flame moss is a unique type of moss that grows upwards instead of horizontally. It has an appearance of a tall flame – but in a bright green color. 

While this is a sensitive plant, it doesn’t require any special care. CO2 supplementations aren’t necessary. Also, you don’t have to feed it, as flame moss is a slow-growing plant that doesn’t require too much energy.

Also, while this is one of the plants that grow on driftwood and rocks, its root systems are rather delicate. Just like with Brazilian waterweed, be very careful with the fish you combine it with.

Scientific name:Taxiphyllum sp. ‘Flame’
Light requirement:Low
Growth rate:Slow
Maximum height:7 inches
Substrate requirements:Any substrate
Nutrition:Optional fertilization
Care difficulty:Moderate

23. Bristly Water Clover

Do you wish to have a cute little clover field in your tank? Then bristly water clover is the right plant for you!

This four-leaf plant makes an adorable carpet inside any tank. Also, it is very easy to care for, as it doesn’t require any fertilization or CO2 supplementation. Still, if you’d want it to grow as fast as possible, you might want to provide it with a bit of both.

Keep in mind that this is a really fast-growing aquarium plant. You might need to prune it a bit after a while. Fortunately, it stays small, so it won’t overcrowd your tank that easily.

Scientific name:Marsilea hirsuta
Light requirement:Low
Growth rate:Fast
Maximum height:1 inch
Substrate requirements:Nutrient-rich substrate, sand
Nutrition:Optional fertilization
Care difficulty:Easy

24. Duckweed

Duckweed is a rather confusive plant as it’s effortless to care for, yet requires lots of your attention – both at once!

This floating plant can survive in almost all conditions imaginable. It doesn’t require any additional CO2, feeding, or even substrate. No matter the light conditions, it will thrive! Truly, I believe that if the end of the world comes, the only things that will survive would be cockroaches and duckweed. 

At the same time, due to its really high growth rate, this plant will quickly overtake your entire tank, taking away nutrients necessary for animal or other plant’s development. Because of this, most aquarists keep it in a separate tank and use it as fish food or for nutrient control.

Scientific name:Lemnoideae
Light requirement:Low to High
Growth rate:Fast
Maximum height:¼ of an inch
Substrate requirements:None
Nutrition:Doesn’t require fertilization
Care difficulty:High

25. Fanwort

Fanwort is a bright green plant that looks a bit like a puffy toilet brush. Many people confuse it with hornwort, but fanwort is fluffier. 

This plant is very easy to care for. You don’t need to provide it with any additional CO2 or feeding. It can get everything it needs directly from the water and soil. 

Fanwort is considered an invasive species in both US and Canada and it is prohibited to toss it in any bodies of water. Fortunately, it is not considered problematic yet, so I don’t see there ever being a chance of keeping it out of the pet stores.

Scientific name:Cabomba caroliniana
Light requirement:Moderate to high
Growth rate:Fast
Maximum height:20 inches
Substrate requirements:Gravel
Nutrition:Optional fertilization
Care difficulty:Easy

26. Aponogeton Crispus

Aponogetons are known as plants that require very little care, and this gorgeous species is no different. 

The only thing you need to provide your aponogeton crispus with is lots of fertilizer. It needs plenty of food to maintain its fast growth. However, it doesn’t need any additional carbon dioxide, other than what the fish in the tank produce.

Also, it can survive most water conditions. You can grow it in both running and still water! However, it seems to prefer fairly shallow tanks in which it’ll thrive and often even flower.

Scientific name:Aponogeton crispus
Light requirement:Moderate
Growth rate:Fast
Maximum height:10 inches
Substrate requirements:Nutrient-rich substrate
Nutrition:Requires fertilization
Care difficulty:Easy

27. Green Foxtail

Another plant with a look that resembles fanwort and hornwort, green foxtail is a fast-growing plant that is very delicate yet really easy to care for. It has feathery leaves that can vary from bright to deep green.

Green foxtail requires lots of fertilization, but it doesn’t need almost any additional care. It thrives in low light conditions and you don’t need to keep it in a nutrient-rich substrate.

As this plant is so undemanding, you can use it for your 40-gallon breeder tank or any other tank that you don’t want to spend any additional time on. 

Scientific name:Haloragaceae
Light requirement:Low
Growth rate:Fast
Maximum height:10 feet
Substrate requirements:Sand, gravel
Nutrition:Requires fertilization
Care difficulty:Easy

28. Rotala Rotundifolia

Rotala rotundifolia is a colorful plant that has many varieties, and all are just as gorgeous. Its exact shade will depend on the amount of light the plant gets, so you might find out that it has changed color over time. 

It doesn’t require any CO2 supplementation, and while you might want to add a fertilizer to support its growth, you don’t really need to do that. This is a resilient plant that can take care of itself.

Just like most other aquatic plants, rotala rotundifolia is considered an invasive species. Be careful what you do with the plant you no longer need.

Scientific name:Rotala rotundifolia
Light requirement:Moderate
Growth rate:12 inches
Maximum height:Fast
Substrate requirements:Sand or gravel
Nutrition:Advised fertilization
Care difficulty:Easy

29. Christmas Moss

Yet another moss that is fairly easy to care for, Christmas moss looks similar to a tiny fir tree and it can make any tank look like it’s ready for the holiday season. It’s usually used as a carpet plant, but it can grow in height, as well.

Christmas moss doesn’t require CO2 or fertilization, but it is picky about water conditions. It needs lots of light and proper temperature to thrive. Fortunately, it doesn’t care about substrate too much, so that’s one less thing to worry about.

While most of us keep Christmas moss underwater, this plant is found above the surface in nature. Still, as you likely couldn’t provide it with enough moisture, it is better to keep it submerged.

Scientific name:Vesicularia montagnei
Light requirement:Medium to high
Growth rate:Moderate
Maximum height:15 inches
Substrate requirements:Any substrate
Nutrition:Doesn’t require fertilization
Care difficulty:Moderate

The Bottom Line

While there’s no plant that truly doesn’t need carbon dioxide, some need it less than others. Sure, there are other things to care about when dealing with plants, but it doesn’t hurt not having to worry about CO2 injections, especially if you’re a beginner. 

Luckily, as you can see, there are many aquarium plants that don’t need CO2 supplementations. 

Still, you need to keep in mind that each aquarium is an environment on its own. The amount of carbon dioxide already present in the water will greatly depend on many factors, such as the number of fish and other living beings inside of it. 

This is why it’s important to always monitor your water parameters and know the state of your tank. Otherwise, your plants and other tank inhabitants might suffer.