Top 10 Easy Freshwater Plants With No CO2

  • May 04, 2021
  • Rita
  •   31        0      0

Do you want a beautiful planted tank but don’t have the funds for an expensive carbon dioxide (CO2) system? Don’t fret, there are plants that don’t require any extra CO2 to flourish. Interested? Let’s take a look at the function of CO2 in your tank, what problems you may experience with such a system, and then finally which plants don’t require this fancy setup at all. 

Why People Use CO2 Systems

Carbon dioxide is used in aquariums to increase the growth rate and health of the plants. Aquariums are closed systems that can’t get access to CO2 like natural systems do, even if you have a lot of fish. Aquarium hobbyist often installs CO2 systems to supplement the tank to improve the following:

  • Fish health

Believe it or not, but CO2 plays a big role in fish health. If there’s too much or too little CO2, your fish might suffer untimely deaths. Fish produce CO2 as they breathe which increases the toxicity of the water and affects the pH. Fortunately, plants in your tank will help to regulate CO2 as well as good CO2 regulators. 

  • Plant health

Your fish and your plants need to exist in a perfect balance to prevent CO2 overload. Plants thrive on the CO2 the fish products along with other nutrients and the fish benefit from the oxygen the plants’ release and the absence of their toxic waste that was absorbed by the plants. Plants that lack CO2 will often look Sickly with pale leaves, stunted growth and will constantly be overtaken by algae. These negative effects can be avoided with a little CO2. 

  • Combating algae  

Plants and algae constantly compete for resources like fish excrements and CO2. When no CO2 is injected into a tank, the algae are usually able to grow and produce faster than the plants can. This results in plants being covered in algae. With a little extra CO2 plants can usually out-compete algae which also keeps your tank clean for longer. 

Problems With CO2 Systems

Carbon dioxide systems aren’t always the answer to your aquarium-related problems, they can also be the cause. Too much CO2 in your tank can cause fish deaths due to raising the pH of the water and turning it toxic. 

It also has to be managed at night. Leaving your CO2 system on during the night can cause fish to die even if the water isn’t toxic during daylight hours. The reason behind this is that plants don’t use CO2 at night since there’s no light for them to photosynthesize. 

If you wanted a low-maintenance tank, CO2 can also cause plants to grow wildly and force you to pay more attention to your tank to keep them in line. Unfortunately, CO2 systems can also be very expensive to set up since you will require the actual system and enough light for your plants to use the CO2 effectively. If you don’t have the budget, here are 10 plants that don’t require CO2 to stay healthy. 

Top 10 Plants That Don’t Need CO2

  1. Java Moss - Taxiphyllum barbieri

Java moss has various purposes and is used by both beginners and expert aquarium hobbyists. It does well in a variety of conditions and is very hardy. Some use it as a cover for rocks or driftwood, to make a moss wall, or just leave it floating. It doesn’t even end there, you can get very creative with this plant. It will need some trimming every now and then but overall, it is a very undemanding plant that doesn’t require CO2.

  • Maintenance level - Low
  • Light requirement - Any type of light
  • Position in the tank - Anywhere
  • Water conditions - Almost any
  • Growth rate - Slow to fast depending on the light
  1. Java Fern - Microsorum pteropus

This is excellent to start within any aquarium. It is very hardy and will thrive in a variety of conditions even without CO2. It does have a few special planting requirements, however. Java fern should never be rooted in the substrate, instead, it should be tied to a rock or driftwood if you want it to survive. It also doesn’t require a lot of light, in fact, too much light will cause the leaves to turn brown. 

  • Maintenance level - Low
  • Light requirement - Low to medium
  • Position in the tank - Anywhere
  • Water conditions - Almost any
  • Growth rate - Slow 
  1. Amazon Sword - Echinodorus amazonicus, Echinodorus bleheri etc.

This plant gets its name from its sword-like leaves. It is on the larger side and more suitable for larger tanks. It is also a fast-growing plant which means it will make a great background plant. This plant does best in medium light, but it will survive in just about any light. Be aware that this plant will die back when you first plant it. Just because the leaves melted away, doesn’t mean it’s dead so don’t just throw it away at the first sign of trouble. 

  • Maintenance level - Low
  • Light requirement - Medium
  • Position in the tank - Background
  • Water conditions - Almost any
  • Growth rate - Fast
  1. Anubias - Anubias barteri, Anubias nana etc.

This plant is one of the few who prefer low lighting above everything else. It is a very slow grower and will usually be left alone by plant-eating fish. Like Java fern, this plant doesn’t like to be planted in the substrate. Anubias tend to grow best when tied to rocks or driftwood. Another good thing about this plant, it doesn’t require any extra CO2 to be healthy.

  • Maintenance level - Low
  • Light requirement - Low
  • Position in the tank - Fore to midground 
  • Water conditions - Almost any
  • Growth rate - Slow
  1. Cryptocoryne - Cryptocoryne wendtii

This plant, like the Amazon Sword, will often die before coming back with a vengeance. Cryptocoryne does really well in low light conditions with no added CO2. There are many different varieties with different colors. 

  • Maintenance level - Low
  • Light requirement - Low
  • Position in the tank - Fore to midground 
  • Water conditions - Almost any
  • Growth rate - Slow
  1. Vallisneria - Vallisneria spiralis, gigantea, etc.

Vallisneria has a lot of subspecies which makes it an ideal plant for just about any tank. They can adapt to a wide variety of light and water conditions. It is a fast grower and will spread by sending out runners from the mother plant. This is a great plant to have if you have relatively shy fish in your tank. 

  • Maintenance level - Low
  • Light requirement - Low
  • Position in the tank - Mid to background 
  • Water conditions - Almost any
  • Growth rate - Fast
  1. Frogbit - Limnobium laevigatum

This is a great plant if you’re looking for a fast-growing, floating plant. It will grow very quickly even in less than ideal conditions creating some shade for your shy fish to hide in. This plant also prefers low lighting and doesn’t do too well submerge for long periods. 

  • Maintenance level - Medium
  • Light requirement - Low
  • Position in the tank - Floating
  • Water conditions - Almost any
  • Growth rate - Very fast
  1. Wisteria - Hydrophila difformis

This plant grows in a variety of substrates making it ideal for beginners. It doesn’t require a lot of light and is quite hardy in a large variety of conditions. It makes a great backdrop for a planted tank. 

  • Maintenance level - Medium
  • Light requirement - Low
  • Position in the tank - Background
  • Water conditions - Almost any
  • Growth rate - Fast
  1. Pennywort - Lysimachia Nummularia

This plant can grow in a variety of substrates and water conditions. It is a fast grower that can easily outgrow algae in your tank. It requires medium light to grow at its best, but no CO2 is necessary for this plant to look great. 

  • Maintenance level - Low
  • Light requirement - Medium
  • Position in the tank - Background
  • Water conditions - Almost any
  • Growth rate - Slow to fast depending on lighting 
  1. Duckweed - Duckweed Lemna Minor

This is a great plant if you want to add some cover for your fish. It grows very fast in the right conditions and floats on the surface of the water. This is one of the smallest flowering aquatic plants used in aquariums. You will have to manage this plant to prevent it from taking over. 

  • Maintenance level - High
  • Light requirement - Medium to high
  • Position in the tank - Floating
  • Water conditions - Almost any
  • Growth rate - Very fast

If you are new to aquarium keeping or starting a new tank on a budget, then these plants will be the perfect specimens to try in a low-light tank with no special CO2 systems. Now it’s time to put your plans into action and make that newly planted aquarium you always wanted. 

About author

Comments

Tagged Articles