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6 Best CO2 Diffusers for Aquariums – Reviews & Top Picks 2021
Carbon dioxide (CO2) is one of the most critical nutrients for the plants in your aquarium. In its purest form, carbon dioxide is a gas. However, much like oxygen, it can be easily dissolved in water. Aquatic plants use dissolved CO2 to photosynthesize in a similar manner that regular garden variety plants would.
It’s worth noting that freshwater aquatic plants take in CO2 and expel oxygen throughout the tank water. They need more CO2 to flourish as to what is already derivable in your freshwater tank.
This is where an aquarium CO2 diffuser comes into play. A CO2 diffuser utilizes reactors or membranes to efficiently dissolve droplets of gaseous CO2 directly into the water inside of the aquarium, creating an ideal environment for your underwater plants to thrive.
There are many different aquarium CO2 diffusers available on the market. But which one is best for you? In this article, we’ll explore the top six best CO2 diffusers of 2020 reviews and offer you a comprehensive buying guide in order to find the right one for your aquatic landscape. Here are our top picks for the best aquarium CO2 diffusers of 2020.
A Quick Comparison (updated in 2021)
|Best Value||Rhinox Nano||
|Premium Choice||NilocG Aquatics Atomic Inline||
|JARDLI Pollen Glass||
|Aquario Neo CO2 Diffuser||
The 6 Best CO2 Diffusers for Aquariums
1. Fluval CO2 Ceramic Diffuser – Best Overall
This ceramic CO2 diffuser boasts a simple design and sturdy, rounded plastic construction. Resembling a tiny black tire, the Fluval CO2 Ceramic Diffuser has a small nipple coming out of the top where you attach your CO2 line. The entire thing can be seamlessly attached to the side of your tank with a suction cup. It’s super simple to install and will not easily break. It’s also extremely affordable, so if you have a few tanks, you can easily buy one for each of them.
It’s kind of an eyesore but luckily the small design makes it easy to hide it behind your fish tank plants. It also does not work well in big tanks and cannot be taken apart for cleaning purposes.
All in all, we think this is the best CO2 diffuser for aquariums.
2. Rhinox Nano CO2 Diffuser – Best Value
The Rhinox Nano CO2 Diffuser is certainly the best aquarium CO2 diffuser for the only. Costing less than $16, this aesthetically appealing CO2 diffuser looks great in any fish tank and is really easy to assemble and install. Rhino uses innovative technology and high-grade material for maximum performance. Moreover, the product’s cylinder shape helps to slow down the speed of your water so your plants can make the most of it.
The one drawback of this diffuser is that it works best in tanks 20 gallons and under. Some buyers have also complained that this diffuser is a tad noisy too.
3. NilocG Aquatics Atomic Inline CO2 Atomizer Diffuser – Premium Choice
Available in an array of sizes to fit any freshwater tank, the NilocG Aquatics Atomic Inline CO2 Atomizer Diffuser is our premium choice CO2 diffuser pick. It’s a breeze to install and can be mounted below or directly to the tank. Producing an ultra-fine mist with an average bubble diameter of less than 0.1mm, this diffuser is easy to clean with a water/bleach solution and is tough to break.
It is on the pricey side of the spectrum. Additionally, when the solenoid cuts off, the product wills with water and sometimes fails. It’s also less pleasing to look at than other CO2 diffusers.
4. JARDLI Pollen Glass CO2 Diffuser
The JARDLI Pollen Glass CO2 Diffuser is a bell-shaped CO2 diffuser that has a built-in bubble counter. Water fills the bell in between the ceramic disk and tube. As the gas exits the tube, it will go through the diffuser’s fine points and creates a bubble. This eliminates the need for separate bubble counterparts. The height is adjustable, allowing it to easily fit in a large number of tank sizes.
It is made completely of glass, making it pretty to look at, but fragile. Additionally, you cannot remove the ceramic disk to clean it or replace it, and the kit doesn’t include a check valve or U-bend.
5. Aquario Neo CO2 Diffuser
This specific aquarium CO2 diffuser is unique to our list because it works with a DIY system. The highly-porous membrane will bubble even in low-pressure fish tanks. Made from a highly resilient clear acrylic, it has all the beauty of a glass diffuser but is a lot stronger. It also comes in small and medium sizes, making it perfect for smaller sized tanks.
The ceramic disk does not come off, so you cannot remove it to clean it or replace it. It also does not come with a check valve, U-bend, or bubble checker.
6. AQUATEK 3-in-1 CO2 Diffuser
The AQUATEK 3-in-1 CO2 diffuser is a compact and versatile aquarium CO2 diffuser that includes a diffuser, check valve, and bubble counter. Made from extra-fine ceramic, it provides an accurate measure of the flow rate while its check valve protects the air pump equipment and gas system from back-siphoning damage. It also will not flood if you lose power. It’s extremely affordable and offers more bang for your buck as it’s a three-in-one product.
Some users have reported that the CO2 was not being diffused properly by this product and bubbles were escaping from the inner silicone gasket circle and ceramic disk.
Buyer’s Guide: Selecting the Best CO2 Diffuser For Your Aquarium
Devices and equipment for your aquarium can add up quickly. This is why it is wise to give your purchases some careful consideration before you buy. You want to ensure the aquarium CO2 diffuser matches your unique needs and style, and also optimally fits your tank size.
There are several things you should think about when choosing an aquarium CO2 diffuser, such as the materials it’s crafted from, the ease of use, the look of it, and its compatibility with your fish tank.
Aquarium CO2 Diffuser Frequently Asked Questions
How does an aquarium CO2 diffuser work? Your aquarium CO2 diffuser works by breaking down large bubbles into smaller ones to be dispensed throughout the aquarium. This will increase the carbon dioxide levels in the water of your fish tank.
How do I care for the diffuser? Aquarium CO2 diffusers are generally easy to care for, use, and operate. However, glass versions must be handled with care because they can break easily.
When it comes to cleaning the device, use a solution of water and bleach, and soak the product in clean water for 24 hours after. When storing your aquarium CO2 diffuser, keep it in a dry and cool area and away from children to prevent damaging it.
Are there different types of aquarium CO2 diffusers? Yes. There are a couple different types, including:
Benefits of Aquarium CO2 Diffusers
Your aquarium CO2 diffuser plays a vital role in the health of the aquatic plants growing inside of your aquarium. They use the CO2 bubbles the diffuser makes as their primary source of carbon.
Some of the perks of using an aquarium CO2 diffuser include:
When all of the aquarium CO2 diffusers reviews are laid out on the line, the best one overall is the Fluval CO2 Ceramic Diffuser. It’s affordable, easy to install, and very durable. The best in value in our option is the Rhinox Nano CO2 Diffuser because it looks great in any tank, super affordable, and made from high-quality materials. It also slows the bubbles down so that your plants can get the most out of its use.
When you’re on the hunt for an aquarium CO2 diffuser, ensure that it properly fits your tank. You can do this by looking at the size of the ceramic disk.
For lush and gorgeous aquatic plants inside your fish tank, it’s important to utilize an aquarium CO2 diffuser to help them get the carbon they need to flourish.
Nicole is the proud mom of Baby, a Burmese cat and Rosa, a New Zealand Huntaway. A Canadian expat, Nicole now lives on a lush forest property with her Kiwi husband in New Zealand. She has a strong love for all animals of all shapes and sizes (and particularly loves a good interspecies friendship) and wants to share her animal knowledge and other experts’ knowledge with pet lovers across the globe.
- A Quick Comparison (updated in 2021)
- The 6 Best CO2 Diffusers for Aquariums
- Buyer’s Guide: Selecting the Best CO2 Diffuser For Your Aquarium