How to use Liquid Carbon in Your Planted Aquarium

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How to Use Liquid Carbon in Your Planted Aquarium

Live aquarium plants require carbon dioxide (CO2) to photosynthesise and generate energy. Hobbyists frequently use pressurized CO2 gas for high-tech plant growth. However, what if they don’t have the budget to invest in a CO2 injection system? Some companies claim liquid carbon dioxide is an effective substitute for CO2 gases, while others argue that it is a chemical treatment to get rid of algae. Continue reading for more information about liquid CO2 and how you can best use it to grow your aquarium.

What is Liquid Carbon?

As part of their plant fertiliser collection, many aquarium companies offer liquid co2 (also known as liquid CO2 or liquid carbon dioxide). It may be sold under the brand names Seachem Flourish Excel and API CO2 Booster in the United States. These products almost all contain glutaraldehyde, or similar chemicals. This is known to decrease the growth of algae in an aquarium. When there is less algae competing for nutrients, light, and carbon dioxide, aquatic plants often grow faster and healthier as a result.

Does liquid CO2 replace pressurized CO2 gas? While liquid carbon is often marketed as a source of carbon, many planted tank experts agree that it is a poor replacement for CO2 gas. In reality, many aquatic plants prefer to grow with their leaves out of water because it is easier and faster to directly access CO2 from the air. Therefore, people set up high tech tanks to help their underwater plants by injecting more CO2 gas into the water at concentrations ranging from 10-30 ppm. Initial studies showed that liquid carbon has a lower level of CO2 than the recommended dosage. In fact, an aquarium that has good surface agitation, gas exchange with an air stone, or filter, results in about 3-5 ppm of CO2 in the water. This is much higher than what liquid carbon seems to provide.

Liquid carbon is often sold as a replacement for pressurized CO2 gas, but we find it more useful as an inhibitor of algae growth.

What is the distinction between liquid carbon or activated? Both are used in filtration systems. Activated carbon is a type of filter media that specifically traps medications, tannins, and other impurities from the water.

Is liquid carbon dangerous to humans? Treat glutaraldehyde as carefully as you would treat bleach. You should not inhale, swallow, or touch the liquid. If you get it on your skin, rinse it off. If you get it in your eyes or mouth, rinse thoroughly for 15 minutes. The website is available for customers in the USA. For Canadian customers, reference

Is liquid CO2 harmful to fish? While we can’t speak for other manufacturers, Easy Carbon is safe for aquarium fish, shrimp, and snails when used as directed.

How to Use LiquidCO2 in Planted Aquariums

Easy Carbon is an algicide that we use to control algae growth in planted aquariums. The algae will return to your tank regardless of how much Easy Carbon you use. Easy Carbon is made up of 1.5% glutaraldehyde (500ml) and 0.5% citric acids. It can be used to treat 5,000 gallons.

How often do I need to use liquid carbon? Easy Carbon can be used as a daily supplement. The pump head comes with the bottle. Low light aquariums will need to use one pump of Easy Carbon (1 ml) every other day. For medium-high light aquariums, use the same dose on a daily basis. If in doubt, lower the dosage and increase it after two weeks of evaluating its effects.

You can also use liquid carbon to treat stubborn algae such as black beard algae. To test the Easy Carbon, shut off the circulation pump and filter. After a few minutes, you can turn on the filter again. If the algae has been affected, you should see signs of weakening and discoloration in 4-7 days. If the spot treatment is successful, try targeting a few more leaves the next week. Do not overdose the tank beyond the recommended amount of liquid carbon or else the plants in the aquarium may be adversely affected.

What plants are sensitive to liquid CO2? Some plants, such as anacharis or vallisneria are known for melting in the presence liquid carbon. If you have sensitive plants like these, consider dosing at half the recommended amount.

While liquid carbon is safe for fish and invertebrates, certain plants like vallisneria may be more sensitive to it.

Why do my tanks get cloudy? Liquid carbon kills algae. This means that small particles of algae may float to the surface of your water. The water can be removed by regular water changes or improved mechanical and chemical filtering.

Why doesn’t Easy Carbon get rid of algae? It is possible that the tank’s lighting or nutrients are too imbalanced. You can reduce your daily lighting by using a power outlet timer for 2-hour increments. Wait at least two weeks before you make any major changes.

You may find that your aquarium has low levels of nitrate around 0-5ppm. This could indicate that your plants are not getting enough nutrients. Follow the instructions to apply Easy Green all in one fertilizer. If your aquarium always has above 40 ppm nitrate, you can reduce excess nutrients from the water by doing more frequent water changes, feeding less fish food, or moving some fish out of the tank.

For more information on plant nutrients, read our full article on choosing the right aquarium plant fertilizer for you. Best of luck with your planted tank, and enjoy nature daily.