Aquarium co2

Aquarium co2 is used by plants during photosynthesis to build new cells for plant growth.  Most freshwater aquatic plants rely entirely on the Carbon Dioxide that is dissolved in the water unless they manage to get leaves above the surface which will allow them to use the Carbon Dioxide in the air.

The things that can restrict plant growth in your planted aquarium are light, Carbon Dioxide and nitrate levels.  The light is entirely within your control.  If you have fish in your tank, the aquarium nitrogen cycle will convert their waste into nitrates which are a natural plant fertiliser, so the only thing that is likely to restrict plant growth is aquarium co2 levels.

Before you hurry out and buy an aquarium co2 system for your freshwater aquarium, make sure that you need one.  Your fish will produce Carbon Dioxide as they breath, breathing in the dissolved oxygen and breathing out dissolved Carbon Dioxide. 

A lot of planted tanks with fish in get by quite happily without additional carbon dioxide so it might be worth trying the tank without first to see how it goes. 

If your plants are growing the way you want then why interfere.  Remember that if you are aerating your tank you are adding aquarium co2 as well as Oxygen.  The other thing to remember is that adding Carbon Dioxide is going to change the pH level in your tank so don’t overdo it.

However if you want to achieve the kind of luxuriant plant growth that you see on the Aquarium Magazines then maybe added Carbon Dioxide is the way to go.  If that is the route that you decide to take then you have three possible options.

co2 Systems for Aquariums - I’ll start with the cheapest first.

The DIY CO2 system.  A Carbon Dioxide bio-system consists of a large soda bottle with a hole cut in the screw top to take a tube.  It is then a case of adding yeast, water and sugar (in small quantities).  This will start to ferment and produce Carbon Dioxide which is delivered to the water via the tube and an air-stone, bubbling up through the water and being dissolved in the process.  Cheap and easy.

A Carbon Dioxide Mechanical system delivers Carbon Dioxide in the same way but uses bottled Carbon Dioxide and usually uses a gas regulator and needle valve.  These are available commercially if you don’t want to go the DIY route.  This would need to used in conjunction with a Carbon Dioxide Monitor to ensure that the levels don’t get too high and start affecting the pH level.

Finally you can get a Carbon Dioxide Electrolysis system which uses electricity to convert a carbon block into gas allowing Carbon Dioxide to slowly bubble off the surface.

All of these systems need to set up to turn off during night time hours.  With the exception of the bio-system this can be done by connecting them to the same timer as the lights so that when the photosynthesis goes into reveres and the plants start producing Carbon Dioxide, you are not adding to it.

But remember, before you go rushing out spending hard earned money on an aquarium co2 system, try it without first, especially with the easy to care for starter plants.

Read about aquarium water testing