Adding CO2 to the water will not help the roots and in fact will hurt them. Plants use CO2 when they photosynthesize, the process which results in the production of sugar. Photosynthesis occurs only in areas of the plant that receive light and contain chlorophyll, the source of plants’ green color. It is absorbed through pores called stomata. Roots have no chlorophyll and don’t ordinarily come in contact with light so they have no use for CO2.
Plants use the sugars they have manufactured as a source of fuel. Their metabolism is similar to the method used by animals. Sugars, which are hydrocarbons, are chemically “burned” in a controlled reaction that occurs when they are combined with oxygen. Energy is released and the waste product CO2 is created.
Both CO2 and oxygen dissolve in water. When water is saturated with CO2 it cannot absorb oxygen so the roots have no source of the element oxygen, which is needed for their metabolism. This weakens the roots and promotes the growth of anaerobic bacteria, which thrive in oxygen-free environments and attack roots.
When water in a reservoir is circulated, it releases the dissolved CO2 to the air and dissolves oxygen. That’s why circulating water in a reservoir using a pump is beneficial to roots: It removes the CO2 and supplies the water with oxygen.
Nutrafin CO2 Natural Plant System Tablets spur the growth of photosynthetic underwater plants.
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