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Flourish Excel Vs Co2 – What’s Better For Your Aquarium?

With planted tank setups being very popular within the aquarium keeping hobby right now, we have seen a large spike in the number of questions being asked about how to correctly maintain a planted tank recently.

Although the general concept of keeping a planted tank is relatively simple, many people overlook the importance of providing your plant with the nutrients that it requires to grow correctly.

Thankfully, this is starting to change and more and more people within the fish keeping hobby who keep live plants in their tanks are starting to use fertilizer and CO2 to help their plants thrive.

This has caused a number of people to reach out and ask for advice on some of these topics and more recently, people have been asking for a Flourish Excel vs CO2 comparison due to both having the same use case but going about it in a different way.

Depending on your tank setup, there are definitely going to be advantages and disadvantages to using Flourish Excel or CO2 and most tank setups will definitely have one product that is better than the other.

This is why we wanted to publish this article going over our own Flourish Excel vs CO2 comparison in a bid to try and help as many of our readers as possible.

What Are The Advantages Of Flourish Excel?

The main advantages of Flourish Excel are that it is a quick and easy way to supplement carbon to a planted tank without causing algae blooms that CO2 can cause.

Depending on the specific setup you have, Flourish Excel can also work out cheaper than a CO2 setup too but this will depend on your tank size and lighting intensity.

As we covered in this article on Flourish Excel, the product also helps your plants improve their iron intake and as we covered in our article about adding Iron to a planted tank, Iron is an important yet often overlooked nutrient.

A deficiency in Iron in planted tanks is very common for beginners and it will commonly stunt the growth of your plants as well as cause issues with your plants yellowing quickly too.

Is Flourish Excel Liquid CO2?

Flourish Excel is technically not a liquid CO2 as it is a synthetic replacement but in most cases, it is easier to just think of Flourish Excel as a liquid CO2 option due to it being so close.

If you are new to keeping a planted tank then it is fine to think of Flourish Excel as a liquid CO2 even though it technically isn’t and the fact that you are helping your live plants with a source of carbon that they are able to utilize is more important.

What Are The Advantages Of CO2?

The advantage of a CO2 system for a planted tank is that it will usually work out much cheaper for larger tanks, especially if they have moderate or high light intensity.

Although a CO2 system is more complicated than Flourish Excel initially, it can offer much more control over the CO2 levels in your tank allowing you to tweak the CO2 levels as required.

This means that as your skills develop and the type of plants you keep in your aquarium advance from the entry-level options, the customization offered by some CO2 systems pushed it ahead of something like Flourish Excel.

An argument can also be made that actual CO2 is easier for most plants to utilize rather than the synthetic version provided via Flourish Excel.

If you are new to keeping live plants in your tank then the difference will probably not be noticeable though and as we touched on earlier in the article, it is more important that you are adding some type of carbon for your plants to use when needed.

Flourish Excel Vs CO2 – For Plant Growth!

Both Flourish Excel and CO2 have been proven to be able to help your live plants in your aquarium thrive.

Either option can work and we usually recommend Flourish Excel for smaller tanks or tanks with low lighting due to it often workout out cheaper and being easier to use while still providing great results.

On the flipside of that though, we would recommend a CO2 system for larger tanks, tanks with moderate or high lighting, and tanks that need an adjustable CO2 level in the water for whatever reason.

Depending on where your aquarium setup lands, one of these will usually be better than the other when following the guidance above.

If you do opt to go for a CO2 system then keep in mind that you may have to take steps to deal with any potential algae growth as a CO2 system can encourage algae growth where as Flourish Excel has ingredients to counter it.

Please also note that some of the cheaper CO2 systems are unreliable and are often too good to be true. If you do choose to go with one a CO2 system then you will usually have to be going with a middle price point system as a minimum and this can push your budget requirements right up.

Are There Any Plants That Are Sensitive To Flourish Excel?

There have been reports of a few plants not responding well to Flourish Excel but the general rule of thumb is that if the plant is sensitive to carbon dioxide then it will also be sensitive to Flourish Excel.

With that being said though, we have never come across any issues when using Flourish Excel with any type of plant and it is generally considered to be a very safe product that can be used with any aquarium setup.

Just follow the dosing instructions on the label of your Flourish Excel or intentionally underdose the product slightly to avoid any potential issues with carbon levels in your tank.