Freshwater Aquarium Cycling: How to prepare for new fish


Aquarium cycling is a process that ensures the tank undergoes nitrogen cycling; therefore, by cycling your aquarium the beneficial bacteria get the chance to grow to a point that they can consume the harmful nitrites and ammonia.

Accumulation of ammonia and nitrates in your aquarium water is all about water chemistry that many people would rather skip. 

Nitrites, nitrates, and ammonia are the byproducts of the uneaten food in the aquarium, bacteria, and algae, also contribute, not to mention the fish and plant waste. The waste therefore, needs to be obliterated or turned into something that can be utilized by other organisms in water, and the reason why we will focus on the process of freshwater aquarium cycling. 

Nitrogenous waste is, normally broken down into four processes, the first one being the release of ammonia after the breakdown of waste. Nitrifying bacteria then converts ammonia to nitrite, Nitrites is also not very safe for fish and is thus converted to nitrate by the beneficial nitrifying bacteria. 

At this point, the levels of toxicity have been reduced and nitrate is absorbed by plants and algae for growth. To keep your aquarium safe from nitrite, nitrate, and ammonia, you will have to adopt the ritual of changing the aquarium water on a weekly basis. 

Freshwater Aquarium cycling

The aquarium cycling process can be carried out with or without fish in the tank. Also cycling with fish is not very convenient because most probably your fish will not be able to live through the process. Though there are some hardy fish that can live through the process, you will most likely stress them out. 

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Beginners in the aquarium industry might make the fatal mistake of buying their tank the same day they purchase the fish, which will then force them to cycle the tank with the fish inside. However, the method that we will be discussing is totally harmless to the fish because they won’t be introduced until cycling is over.

Introducing ammonia

Ammonia in water forms because of the accumulation of different types of waste, but your new tank doesn’t have fish that will help generate waste. The solution, therefore,  is simple and all you need to do is for every 12hours you will have to introduce fish food and leave them to disintegrate so that it can help in the production of ammonia.

Check for ammonia presence

After initiating the above process you need to make sure that things are going as planned and the levels of ammonia are reaching an all peak high. By using a test kit you could check the levels of ammonia after every few days, and you should ensure that they don’t go below 3 parts per million. 

The latter should be maintained and in any case, you realize that the levels have dropped beyond the recommended level, add more fish food and leave them to decay and disintegrate. The second process should not exceed one week. 

aquarium water test

Check for the presence of nitrites

The aquarium cycling process entails using a number of test kits for effectiveness, the ammonia introduction phase only goes on for one week after which you will now test for the presence of nitrites in the water, which will be a sign that the cycle has started. But this should not stop you from adding the fish food in water. 

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Check for the presence of nitrates

The presence of nitrates in the aquarium water is an indication that the cycle is almost complete, and at this point, you will notice that the levels of nitrites and ammonia begin to drop. When they reach zero it is an indication that the cycling process is complete. You will, however, have to check on the levels of nitrate and if they are high or above 40, then you will have to reduce that number by changing some of the water. 

Add your fish 

So now that the aquarium is free of nitrite and ammonia, you can introduce your fish; the process is gradual whereby you introduce new fish within a two-week difference. You will also have to ensure that your aquarium is clean; a hose should do the magic and get rid of any waste that might have lodged itself in the substrate. 

The problem with hidden waste in the substrate is that it will not have any effects immediately but will erupt rather badly when tampered with in the future and release a huge dose of ammonia. 

water change aquarium

Possible nitrogen cycling problems 

Failure of the aquarium to start cycling: there are some people who have had problems with the cycling of ammonia where they fail to cycle. In normal circumstances, ammonia will be detected on the third day, so if the following days don’t register any ammonia then it is possible that the tank may not be cycling. 

The above could have been caused by a lack of an ammonia source or there is another organism in water that is feeding on the ammonia rather fast that makes it impossible for the bacteria to get to it. You can, therefore, introduce some ammonia in the tank or reduce the number of plants in the tank. 

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Failure of the ammonia levels to go down: if you are cycling your new aquarium then avoid over-cleaning it, ensure that the PH is not too low, and don’t use chlorinated water. The above are some of the most common causes of your PH to remaining stagnant. 

Stagnant nitrate level: using chlorinated water in the aquarium is one of the surest ways of killing nitrates in your water tank. Cleaning too much also has a negative impact during aquarium cycling, it is common knowledge that the necessary bacteria live in filters and gravel, so when you clean too much you remove the necessary bacteria.

Lastly, there are many methods that can be used in the cycling of an aquarium, so complete cycling cannot be really guaranteed with the different methods. You could also adopt methods that will help shorten the process, but to be on the safe side, it would be best if you tested the waters from time to time and change the water.

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