Nutrients for aquatic plants can be generally divided into two groups. They are mineral nutrients and non-mineral nutrients. There are mainly three non-mineral nutrients that are absorbed by aquatic plants. They are Carbon (C), Oxygen (O) and Hydrogen (H). Plants absorb these nutrients in the form of CO2, O2 and water (H2O) itself.
We can’t imagine life without carbon. Every organic structure has carbon and hydrogen. Plants generally absorb carbon in the form of CO2. Various aquatic plants also absorb hydrogenous carbonate ions (HCO3–) as a source of carbon. So, every aquarium needs carbon. It is a vital element for the growth of aquarium plants. If there is a deficiency of carbon in the aquarium, the plants will start to melt away, leaves will turn pale, the growth rate will slow down and stems will become weak. You can add carbon to your aquarium in various ways. The best way is to set up a pressurized CO2 system. But this method is costly and not suitable for small tanks. For small tanks, the best choice is to go for liquid carbon. They are cheaper than a pressurized CO2 system. But if you want to spend the least amount of money, you can go for DIY CO2 system. Though it costs next to nothing, it’s not as effective as liquid carbon and pressurized system.
Water itself is the source of hydrogen. Hydrogen gets split from water molecules during the reaction of photosynthesis with the help of light. This reaction is named Photolysis and oxygen is produced from it. During the dark reaction of photosynthesis, hydrogen as H+ is built into organic elements.
Many organic compounds have oxygen in them as a basic component. It is extremely important for aerobic respiration. Aerobic respiration uses Oxygen and releases CO2 in return. The oxygen that is built into the organic compounds comes from CO2, as does carbon. If there is a deficiency of oxygen in the water column, the fishes will come at the top of the water surface. If there is a long-term deficiency, plants will become stunted and algae bloom may occur. If there is an oxygen deficiency in the water, check your filtration system, fish population, lighting and all other maintenance procedures. Make any adjustments if needed.
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