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Adding CO2
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Want a planted tank with fantastic growth?

Aquatic plants require three main factors to not just survive, but to thrive. These three factors are light, nutrients-fertilizers, and CO2. Light and nutrients are typically the easiest of the three to provide. However, in order to allow for lush, rich plant growth, providing adequate CO2 is the key. In order to do so, some sort of CO2 injection system is required. Certainly, there are many aquarium hobbyists who do not give their plants any sort of special treatment and still end up with a fairly nice display. However, truly luxuriant growth, the sort that you see on the covers of aquarium magazines and in pictures of tanks created by Takashi Amano, can only be achieved by adding CO2.

During photosynthesis, plants use light energy to capture CO2. This CO2 is used to build the basic carbon structures from which all plant material is made. In a poorly lit aquarium, light is likely to be what limits the rate of plant growth. The amount of CO2 produced by fish- and bacterial respiration is more than enough to allow photosynthesis under these conditions. If on the other hand, you try to make your plants grow faster by adding more light, it is likely that there will not be enough CO2 in your aquarium. The plants simply can not grow as fast as they would like to, given the available light energy. Most tanks are poorly lit, however if you have upgraded your lighting for plants, CO2 may be your next investment. With nine tanks that are all moderate to heavily planted, I use each of the methods I will discuss here. My favorite is of course the most expensive of the options, the pressurized system.

A pressurized system consists of a CO2 tank, regulator, needle valve, bubble counter and some type of reactor. I also have a solenoid and automatic Ph monitor on mine which allows you to set the Ph to a specific value and the unit will disperse CO2 until that value is maintained. While most tanks, regulators, needle valves and bubble counters are pretty much the same, the reactor can be anything from a glass blown bell which traps the CO2 inside allowing it to dissipate into the water, to a powered reactor which uses a powerhead and a chamber to mix the CO2 into the water. The pressurized system can run about $300.00, however a 20 lb tank will run a large aquarium for about a year. This is the most effective system available.

A store bought mix system like the Hagen Natural Plant System is designed to supply any aquarium with a safe, economical, and efficient method of providing CO2. It uses a natural fermentation process for creating CO2 and allows quick, easy, and affordable refills of ingredients to provide continuous CO2 for a 3-4 week period. The fermentation canister was developed to support consistent carbon dioxide output. The ladder style counter/diffuser allows the CO2 gas to be dissolved into the water. This type of CO2 system is effective for aquariums up to 40 gallons per unit.

A Do It Yourself (DIY) system may not look as nice, but if you plan to keep the bottles under the cabinet, it won’t matter anyway. The DIY method uses simple materials (soda bottles, silicone tubing, check valves, fittings) to create and deliver a home brew of CO2 gas to your tank. You can use a reactor or simply place the end of the tubing in your filter intake, the bubbles will be churned by your filter, however this can be noisy.The most important step is the mixture that provides the CO2. For two-liter bottles, our favorite mix is:
6 oz pack of Jello (your choice of flavor)
2 cups boiling water
1 cup cold water
2 cups sugar
1/2 cup lukewarm water
1/2 tsp Active Dry Yeast
Dissolve the Jello in the boiling water, add 1 cup cold water and pour into 2 litter bottle, place in refrigerator overnight. Next day add the yeast to the lukewarm water to activate it, then pour into the 2 litter bottle and cap. This will start producing CO2 in a few hours, do not shake the bottle or you will get too much CO2. Each bottle will produce CO2 for about 3 weeks. There are also other formulas for CO2 production, the Jello mix has proven to be the most consistent we have tried so far.
Good Luck and Happy Plant Growth!



Posted by my fish not me


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