CO2 Tank and Regulator

Plants and CO2
Source: http://www.qsl.net/w2wdx/aquaria/diyco2.html

Carbon is the fundamental element that all life on this planet is based. Plants are no exception. Since plants have no way of getting to their food sources, nutrients have to be obtained from their surrounding environment. Plants use many macro and micronutrients, carbon dioxide (CO2) being one of the primary macronutrients. In an aquarium the limiting factors are most likely to be (in order): light, CO2, micronutrients (trace elements), and macronutrients. Micro and macronutrients are usually supplied in adequate quantities by fish waste and the addition of fertilizers.

Plants use a process known as photosynthesis to produce the carbohydrates they need for life. Photosynthesis requires light for energy and CO2 to drive the chemical reactions. The process of photosynthesis requires a specific light energy threshold. In other words, there is a point where light has reached a specific intensity to start photosynthesis. If the light is not bright enough, photosynthesis will not occur. Beyond that threshold and up to some high light level, photosynthesis will run faster and faster. According to known practice, when light levels exceed two watts per gallon, supplementary CO2 is required for most aquariums.

In our planted aquariums, CO2 is present without it being added my mechanical means. Fish respire CO2 from their gills. Also in an aerated tank, CO2 from the atmosphere is dissolved in the water. This effect is known as atmospheric equilibrium. In nature though, CO2 levels are usually higher than can be explained by animal respiration or atmospheric equilibrium, and aquatic plants have evolved to this higher concentration of dissolved CO2 in water. Carbon dioxide rich groundwater often feeds the streams and natural CO2 concentrations up to several hundred times atmospheric equilibrium are common. In general, aquatic plants like to see approximately a concentration of 10-15ppm of dissolved CO2 in their environment. CO2 levels from atmospheric equilibrium are generally around 2-3ppm. (ppm stands for part per million). As you can see, CO2 injection is essential for vigorous plant growth, and even more so with higher light levels.

It is a common misconception that water can hold only so much dissolved gas and adding CO2 will displace oxygen. This is not true. As a matter of fact, if enough CO2 and light is present to enable vigorous photosynthesis, oxygen levels can reach 120% of saturation. Even at night, when the plants stop using CO2 and start using oxygen, the oxygen levels will stay about the same as a typical non-planted aquarium. So reports of people having fish at the surface gasping for air is not necessarily a result of high CO2 levels, but instead a lack of oxygen in the water is probably the culprit.


The relationship between light and CO2 levels is important. The diagram at the right explains it conceptually. At low light and low CO2 there is not much energy to play around with for up or down-regulation of the pools of Chlorophyll or enzymes contained in the plant. If we then add a little more CO2 to the system the plant can afford to invest less energy and resources in CO2 uptake and that leaves more energy for optimizing the light utilization - Chlorophyll can be produced without fatal consequences for the energy. Hence, although we have not raised the light, the plant can now utilize the available light more efficiently. Exactly the same explanation can be used to explain why increased light can stimulate growth. with more light available, less investment in the light utilization system is necessary and the free energy can be invested into a more efficient CO2 uptake system so that the CO2, which is present in the water, can be more efficiently extracted.

Providing macro and micronutrients to plants is easily done with commercially available fertilizers. It is often a more difficult and expensive task to provide adequate light over the plant aquarium. Both numerous fluorescent light and halide lamps will produce sufficient light if supplied with effective reflectors, but in deep aquaria (more than 20 inches) is very difficult to offer enough light to small light demanding foreground plants. Based on known experiments, I suggest commencing CO2 addition before any other action is taken! I believe that even at very modest light intensities you will experience a conspicuous change in plant performance in your aquarium. The exact amount CO2 may always be discussed but concentrations from 10-15ppm will only improve plant growth. You will probably see that plants, which were barely able to survive before now thrive in the presence of CO2. These conclusions were derived from work conducted by Ole Pedersen, Claus Christensen, and Troels Andersen.


Mr. Aqua Co2 Tank

• soild aluminum bottle with metal hook
• made from aluminum alloy - anti corrosion bottle against acid, alkaline and oxidation
• equipped with a regulator and valve.
• easy to refill

Sizes available: 0.52 liter, 0.6 liter, 1.0 liter, 1.45 liters

Price:
0.52 liter with CO2 regulator
1.0 liter with CO2 regulator
1.45 liter with CO2 regulator

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Mr. Aqua Aquarium System Philippines
Email: boniface_lan@yahoo.com

Wholesale are welcome!!