CO2 in the Planted Aquarium – A Necessary Luxury

This is a picture of us using CO2 in the Planted Aquarium

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It has been about 4 years since we discovered our fascination with the art of aquascaping. We watched hours of YouTube videos by James Findley from the Green Machine, George Farmer, Oliver Knott, and of course Aqua Design Amano. After carefully studying how these masters of aquascaping created living works of art contained within 4 walls of glass, we decided that we were ready to take on the challenge ourselves.

If you read the article we wrote about our setups, you will see that we have both CO2 and non-CO2 injected tanks. I mention this because I want you to know that CO2 in the planted aquarium is not necessary in all applications, but is a must in others.

When we set up our first scape, we thought we had it all figured out. Yes, we watched YouTube videos until the cows came home, but there was one critical ingredient that we neglected to add, CO2. We didn’t really neglect to add it. This was a conscious decision based on the fact that after we purchased all the high-end equipment, tank, stand, lights, substrates, hardscape, plants, etc., we were into this hobby for about a grand.

We thought we’d be able to use Seachem Flourish Excel as a CO2 supplement, but that was not enough to keep a proper balance between high light, nutrients and CO2. I guess you could say our first scape was a lesson learned the hard way. So even after using all the right substrate materials and purchasing a Current Satellite Plus Pro LED light, the tank still bombed.

Here is a picture of that first scape after a water change at 5 months maturity…

This is a picture of our 8 gallon Mr. Aqua Low Iron Rimless aquarium with no CO2 injected

And here is the same scape one week after a water change…

This is a picture of our 8 gallon Mr. Aqua Low Iron Rimless aquarium with no CO2 injected that has a big BGA problem

As you can see, we had a serious problem with Blue Green Algae (BGA) and Green Dust Algae. I spent a considerable amount of time reading the Barr Report and trying to figure out EI (estimated index) dosing for fertilization. I wasn’t able to grasp the concept at the time. While trying to learn about plants, substrate, lighting, and all of the various other tidbits involved in setting up a successful scape, my brain was struggling to process the huge amount of information I was packing in.

When I tried to  set up a dosing regimen, all I managed to do was create the issue that you see in the above picture. Without CO2 in this planted aquarium, it was a losing battle to begin with.

This is a picture of our new CO2 cylinder and regualtorAlmost a year after the initial setup, we ended up tearing it down, cleaning everything with peroxide, and starting from scratch. I purchased a nice little 5 pound cylinder from Amazon and a Milwaukee regulator from Phoenix Tropical Fish.  We bought a check valve and drop checker from another LFS, and a cool little inline diffuser from Amazon. Once I researched how not to gas my fish to death using CO2, we were off and running and never looked back.

To get back to the point of this article, the addition of injected CO2 in the planted aquarium is a must for certain setups. It is not necessary in low light conditions with plants that thrive in those conditions. But if you want to grow compact carpeting plants like Monte Carlo and Dwarf Baby Tears quickly and without serious algae problems, it is necessary.  With CO2 added to our high-light tanks, we have seen optimal plant growth and little to no algae problems (considering the number of setups we have).  Our tanks are lush and the plants are pearling and happy.


This is a picture of a happy and healthy CO2 injected planted aquarium

I know that when first starting out in this hobby it’s easy to spend a small fortune, so don’t worry if you can’t afford a decent CO2 system. I want to reiterate, you can grow carpeting plants without the addition of CO2. I read an informative article written on the Expert Aquarist blog by Anne Thynne that explains step by step on how to nurture these plants to a decent carpet without using CO2.

Whatever you do, when it comes time to invest, don’t skimp on cheap equipment. It will only make your life difficult and the hobby less enjoyable. Learn from my mistakes.

I’ll write a detailed article in the future on exactly how we implemented our CO2 systems. Setting up and maintaining a micro ecosystem is a never ending and ever fascinating journey that will take you down a path of delight, wonder, and at times, frustration. In the end, the work of art you create in your world will bring satisfaction and harness a bit of nature that can be enjoyed for years.

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