Basic: Nitrogen Cycle and why it is important in our aquarium

Nitrogen Cycle is one of the most important things to be understood by any aquarium owner. Yet it is usually being overlooked. That is why there are many cases like New Tank Syndrome or fishes dying immediately.

Nitrogen Cycle is a very big and complex topic. In this article, we will explain only the basic part about Nitrogen Cycle that must be understood by any aquarium owners.

What is Nitrogen Cycle?

Nitrogen Cycle is the process to break down highly toxic Ammonia (NH4+) to highly toxic Nitrite (NO2) and then break down again to least-toxic Nitrate (NO3) by a lot of different type of “good bacteria”.

Why do we need Nitrogen Cycle in our aquarium?

Highly toxic Ammonia is introduced into the tank as fish waste, decomposed matter and etc… It will stay in the aquarium with your fishes and caused harm to your fishes. Although you can take out this ammonia by doing water change but they can kill your fishes within a very short amount of time and you will not have enough time to react.

This is where Nitrogen Cycle comes in. This process will break down highly toxic Ammonia (NH4+) all the way to least-toxic Nitrate (NO3) by the “good bacteria”.  This process is one of the most important things that will keep your fishes alive.

How do we introduce Nitrogen Cycle into our aquarium?

Nitrogen Cycle is a process where a lot of different bacteria come together to break down Ammonia all the way to Nitrate.

To introduce Nitrogen Cycle is to introduce these bacteria into the aquarium and make them multiply to a large number that will break down Ammonia fast enough to prevent any harm to the fishes

These bacteria will start to grow and multiply as soon as you add chlorine-free water into your aquarium. But it will need time for these bacteria to grow to an amount large enough to break down Ammonia fast.

Basically, it means you will not be able to introduce fishes immediately after you set up your aquarium and you will need to keep your aquarium fishless until you get these bacteria to multiply.

How long before we can introduce fishes into our aquarium

A standard guideline will be around 3 weeks before you add any fishes into the aquarium.

Of course there are methods to accelerate the process.

There are ready bacteria products that you can buy off the shelves and it greatly speed up the process. These products introduce bacteria into the aquarium and increase the amount bacteria in the aquarium in large quantity so bacteria will multiply much faster.

 JBL Denitrol

We find this method the most convenient and fastest to be used by aquarium owner. Usually fishes can be introduced into the aquarium within 3 – 7 days.

Read article: how to introduce fish into aquarium? (coming soon)

Now we are done with Highly Toxic Ammonia, we got to deal with least- toxic nitrate now.

Things do not end with Ammonia being breakdown to Nitrate. 

Nitrate is the least harmful and will not harm fishes in low concentration until its amount accumulates. In an aquarium, Nitrate is usually the final product of the Nitrogen Cycle and it will not break down any further.

The easiest way is to manually take out this nitrate by doing water change to keep the amount of nitrate in our aquarium at low concentration so it does not harm our fishes and this is usually the reason why we keep telling you to do water change.

Read article: When do we need to do water change? (coming soon)

"Keeping an aquarium is more than keeping fish. We are keeping a natural habitat environment for the fishes to live in and this natural habitat is what makes keeping an aquarium fun. In nature, these natural habitats are not created overnight, they are created over a period of time and it is the same to your aquarium."

Once again, this article does not explain everything of Nitrogen Cycle but only a small part of how it helps in your aquarium and why it is important. Please do research more if you want to understand more on this topic.