The Nitrogen Cycle Explained

Date Posted:26 January 2022 

The Nitrogen Cycle Explained main image The Nitrogen Cycle Explained image

All you need to know about the nitrogen cycle when setting up an aquarium

Beginners in fishkeeping usually do not even know about the nitrogen cycle and its importance. Then they are shocked when aquarium water suddenly gets cloudy or green with algae. In most situations, this happens because of disruption in the biological balance. That's why your aquarium must have an established nitrogen cycle before any fish are introduced into your aquarium, regardless of how large or tiny your fish tank may be.


When fish are transferred to an aquarium, they immediately start producing ammonia into the water through excreta leading to bacteria flourishing that transforms it into nitrites. The nitrites then are transformed into nitrates by other colonies of bacteria. The nitrates can accumulate in the aquarium and be deadly to the fish in significant quantities. 


The nitrates are disposed of in a couple of ways. The first way is when plants absorb these nitrates and make oxygen through photosynthesis. Another way is by doing weekly water changes. Fishkeeping can be an art and If you would like to learn many things about aquariums. Reading articles on our site is the best way to start your journey in the fishkeeping hobby.


If you transfer fish to your aquarium too soon, without proper preparation, a very high probability exists that your nitrogen cycle is still not established. If such a situation occurs, any fish, shrimp, and crabs can get ammonia poisoning and eventually die. This article will teach you how to set up your aquarium without endangering your fish. 


As you probably already guessed, the poisonous compounds that fish induce are biologically cleaned by various colonies of helpful bacteria. They dwell in every part of the aquarium, like on the filter, on the surface of the glass, and the substrate.


In addition, ammonia does not appear only from excretions. Because the fish are fed on a regular basis, parts of the food are usually not consumed and left floating or get stuck in the soil. After a while, ammonia gets generated when the food begins to disintegrate and rot. The same thing applies to rotting plants and dead fish.


At the end of the nitrogen cycle, ammonia is converted into nitrates that have to be removed regularly. The nitrogen cycle is a permanent state of equilibrium between nitrates being nutritious to plants and them being harmful to fish.


Live aquarium plants are strongly suggested for every fish tank since they absorb nitrates. Hence aquariums with plants require less care, making it appear more natural and providing hiding places for fish, which helps to reduce their stress. There are a variety of approaches that may be used to jumpstart the nitrogen cycle in a fresh aquarium. Keep reading.


We always say it’s a good idea to purchase water testing equipment and do tests at various stages of setting up your aquarium.

The traditional way of setting up an aquarium - more time-consuming.

This method simply needs more time. You only need to set up and equip an aquarium, decorate it, add plants, and turn on the light. That's it. You will now need to keep track of the water parameters in your aquarium and wait until the biological balance and nitrogen cycle reaches equilibrium. It usually takes around two weeks to complete. Your aquarium may grow cloudy, which is caused by a bacteria outbreak. This is a part of the nitrogen cycle. It is entirely normal.


After the first week, test for nitrites and then, after two weeks, for nitrates. You can start thinking about transferring fish in your aquarium when the ammonia and nitrites levels get low, and the nitrates level gets higher. Do a 30% water change before moving the fish.


It is not a good idea to put 20 neons into 20 liters. This will cause the biosystem to become overwhelmed and, ultimately, lead to fish death. That's why it is generally better to start with a big aquarium of 50 liters for beginners. This is because it is easier to set up and maintain the nitrogen cycle bigger ones, unlike in smaller and nano aquariums. Add fish gradually. At first, only a few, then more. Here are the rules for planting fish in an aquarium.


Place a bag with fish in your aquarium. Let it float for between 10-20 minutes until the water temperature in both the bag and the aquarium gets equal. To balance the water parameters, open the bag slowly and start adding aquarium water to it. Begin by adding 25% to the bag. After half of the hour, add another 25% until the water in the bag is entirely from your aquarium. Now you can place fish into the aquarium. It would be best if you kept an eye on them for a couple of hours if any problem occurs, as they are under big stress. 

This second method - modern and fast.

You will need special water treatments to bootstrap the nitrogen cycle establishment for this method. After you have filled the aquarium with water, you need to add special mixtures like Aqua One Bio Starter appropriate for the size of the aquarium. Aqua One Ammonia Chlorine Neutraliser can be added to the aquarium water when you are doing a water change. It protects the fish's gills by removing heavy metals from tap water.


Once you have added these water treatments for a startup, wait a day or two, and you can start adding fish. This process is no different from the first method. You will still have to observe the behavior of the fish. If the fish are breathing fast, if the gills have an unnatural color, if the fish attempt to swallow oxygen from the surface of the aquarium, then they may have ammonia poisoning. In this situation, it is best to move them to another aquarium and wait until everything is normal.


Your aquarium depends on the nitrogen cycle. Your pets' health and their life expectancy depend on how balanced it is. Modern methods make it easy to set up an aquarium, even for children. It would be best if you took proper care of your fish and never planted them in an aquarium with not yet an established nitrogen cycle. This article should help you safely set up your first aquarium and plant fish.



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