CO2 in Planted Aquaria

CO2 is beyond comparison the most important of all plant nutrients. Without sufficient CO2, plants cannot photosynthesize and convert into energy-rich sugars, starch and all the other carbon-containing molecules that constitute a plant. It may seem odd to look at CO2 as a plant nutrient. When growing terrestrial plants, we are used to providing light, water and nutrients, but never CO2. is article explains why we need additional CO2 in the planted aquarium, how CO2 is used by aquatic plants, how we can supply CO2 and how much CO2 they need. CO2—the most important plant nutrient CO2 is the most important plant nutrient because of its role in photosynthesis, eventually leading to formation of new leaves and roots. Photosynthesis is a process that is only mastered by photoautotrophs, i.e. organisms that can live with light as the sole source of energy. In photosynthesis, carbon dioxide (CO2) and water (H2O) are converted into energy-rich sugar (C6H12O6) and oxygen (O2) by means of light energy (see Box 1 on page 26).