Planted Tank Essentials: Injecting CO2

There are many ways to provide CO2 into your aquarium.

Pressurized cylinder systems using refillable tank and solenoid valves to control its flow are the most common ones specially on large aquariums. This is the most convenient solution but the most expensive as well.

Another way to provide CO2 is to use a dissolved or liquified CO2. It can be purchased in aquarium shops and can be dosed off to your tank the daily at an appropriate amount fit to the size of your tank.

I use a "Do-It-Yourself" CO2 reactor. In this system, yeast is mixed with sugar, baking powder and water in a sealed container and a fermentation process begins when the yeast starts to convert the sugar to alcohol, giving off CO2 in the process. The CO2 is forced out of the container and a long a tube into a smaller bottle with water to hold off any toxic chemical that may come out with the CO2 gas from the sealed container. The CO2 in the bottle will bubble up and move along another tube into the aquarium, where it can be dissolved into the water through the use of a diffuser.

"DIY" CO2 Reactor

Although this is not the best method of providing CO2, it is very cheap to build and easy to implement. It is great for use on smaller tanks at around the size of 100 liters or less. The only drawback is that you don't really have an easy way to control the amount of CO2 you inject in the tank as with the pressurized systems where electronic timers can be used to control the CO2 dosing automatically.

In my current solution, I used the recipe below which is expected to last for one week before it can be refilled again.

2 Cups of sugar
1.5 Liters of water
0.5 table spoon of baking soda
1 table spoon of dry baker's yeast

At the moment, I am observing its performance to see if it can really last that long. I will provide details on the results on my future posts.