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Aquarium CO2 Refill Bottles

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Help and advice on shopping for: Aquarium CO2 Refill Bottles

Boost the health of both fish and plants

In a planted freshwater aquarium the correct levels of CO2 are essential for healthy plant growth. CO2 bottles are compact and efficient, providing your planted aquarium with the right amount of carbon dioxide for lush growth and beautiful results. Find top brands like JBL, Tropica and Fluval here at Swell UK.

What are CO2 bottles?

CO2 bottles are perhaps the cheapest way to add CO2 to an aquarium. They consist of a pressurised CO2 can, a hose, and a diffuser. Press the button on the can and the diffuser fills with CO2 gas. When in contact with water, the gas is soaked up from inside the diffuser chamber until the gas is gone, and the diffuser is full of water. Press the can again, fill the diffuser, and the whole process is repeated. The more commonly used CO2 bottles are plugged into a CO2 regulator which is used to dose the CO2 very slowly through a CO2 reactor, CO2 diffuser, or bubble counter. The cheaper can versions are generally only used on small aquariums.

Why should I buy CO2 bottles?

CO2 gets depleted over time, so you will need to either replace or refill your CO2 canister regularly in order to maintain a healthy CO2 level for optimum plant growth. CO2 bottles ensure your aquatic plants get a healthy and regular dose of carbon dioxide to help them feed. Most aquarium plants do not thrive without CO2 fertilisation - but algae may. So without extra CO2, your new plants can suffer and algae could take over your tank.

What are the main types of CO2 bottles?

Carbon Dioxide products vary in price, complexity and effectiveness, and they come in two main forms: cheap disposable CO2 canisters that work like aerosol cans and refillable CO2 bottles that work with a CO2 regulator to control the output of CO2. CO2 bottles come in a variety of sizes. The larger the bottle, the longer it's going to last you. A larger bottle also becomes more economical to fill up, saving you money in the long term. CO2 bottles include disposable cartridges and the larger, more sturdy steel CO2 bottles have an external shut off valve and are supplied with a safety cage.

What accessories should I buy with CO2 bottles?

Although carbon dioxide can be overdosed with plants, with no side effects, the same cannot be said about fish. Add too much CO2 to your aquarium and your fish may die, so it's another good reason to invest in a kit with a good, precision regulator, and a CO2 test kit.