Thursday, December 22, 2016

Importance of Nitrogen for Healthy Aquatic Plants

nitrogen for planted tank

Besides light and carbon dioxide, Nitrogen is the most needed element by aquatic plants to grow healthy. After carbon, this is the element plants need the most amounts. A nitrogen deficiency results in slower growth of aquatic plants, which is also the reason for algae growth.

Why plants need nitrogen?

Plants require nitrogen for hundreds of things. As an example, all amino acids have nitrogen in them. Amino acids are the building blocks of proteins, without which no life can sustain. Nitrogen is also an important part of chlorophyll, nucleic acid and plant hormones.

The air we breathe has 78% Nitrogen in the gaseous form, but plants are unable to use it in the gaseous form. The most usable state of nitrogen for aquatic plants is ammonium (NH4) and Nitrate (NO3). Some plants can also absorb nitrogen that is in the form of urea (CH4N20). The nitrogen cycle is very important for both terrestrial and aquatic plants. This cycle explains the conversion of ammonia, nitrate, nitrite, ammonium, urea to gaseous nitrogen, which is performed by a bacterial colony.

Sources of Nitrogen in an aquarium:

In the aquarium, leftover fish food, various organic compounds, fish waste, etc. degrades and produces ammonium. A good bacterial colony will convert it to nitrate by this process: Ammonium à Nitrite à Nitrate. This organic source of nitrogen can often be insufficient for a heavily planted tank.

How plants use nitrogen?

Some species of aquatic plants prefer nitrogen in the ammonium form, while some other species prefer it in nitrate form. Some plants even use both of these forms. It takes a lot of energy to convert nitrate into ammonium, however, vacuoles in the cell of the plants can store nitrate ions and they have high transportation speed within the plants. Unlike nitrate, ammonium is never stored within the plants. They are used right away or converted to nitrate by a bacterial colony. If the pH of the water becomes more than 7.5, ammonium can turn into ammonia, which is poisonous and also the reason for high algae growth. High level of nitrate forms inorganic sources such as Potassium Nitrate 
(KNO3), which is not poisonous for many organisms in the planted tank.

Nitrogen Deficiency Symptoms:

=>Plants turn to yellowish color. The older leaves become more yellowish than the younger ones, though the older leaves do not die.

=>Smaller leaves becoming lighter in color is also an indicator for nitrogen deficiency.

=>Nitrogen deficiency also results in a very slow growth rate of aquatic plants.

=> Some species of plants may show a reddish discoloration.

How to provide Nitrogen?

Aquatic plants absorb Nitrogen from Nitrate (NO3). Potassium Nitrate (KNO3) is a good source of nitrate. You can buy Potassium Nitrate powder and mix water to make your own Nitrogen supplement. However, you should only do it if you are comfortable with precise measurements. The supplement needs to be of right concentration for using in the aquarium. Some hobbyists also use Potassium Sulfate.

If you are not comfortable with the above method, you can easily buy nitrogen supplement products from the market. Seachem Flourish Nitrogen is used by many aquarists for supplementing nitrogen to the aquarium. You can check out the product here!

Like Nitrogen, Iron is also often used by the aquatic plants. Click here to know the importance of Iron in aquarium, its deficiency symptoms and the way to provide Iron in your aquarium.

Comment below if you have any question and I’ll try to answer as soon as I can!


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