Cycling a Fish Tank

Nothing is more tempting than buying new fish for your freshly set aquarium. Seeing the new creatures swirling around is very soothing. However, cycling your fish tank before introducing the new fish is very important. The fish may suffer severely if you do not cycle your tank and give them entry. The chances of fish coming under stress and eventually dying are very high. 

New aquarists often face this situation. It could be really devastating and demotivating seeing your new bunch of fish suffering. However, such unnecessary deaths of fish can be prevented by cycling the aquarium, especially before introducing new fish inside it. It is essential to turn the toxic environment of the aquarium into a healthy system for sustaining the life inside it. 

The entire process of converting the toxic stage into a healthy system takes time and is called the nitrogen cycle. The colonies of beneficial bacteria turn the wastes into less harmful substances establish in the filter and gravel. Unfortunately, this process of conversion takes time. Therefore, it is essential to know the right time to add the fish, for which you need to understand the nitrogen cycle first. 

Nitrogen Cycle 

Ammonia is released into the water with the fish feces, leftover or uneaten food particles, rotten and decaying plants. When these substances start breaking down, NH3 or ammonia releases that trigger the nitrogen cycle and the growth of beneficial bacteria. If you test the water of an uncycled tank, you will see how the level of ammonia shoots up by the third or fourth day. 

Since ammonia is very harmful to the fish and other aquatic inhabitants, its level should always be kept at 0 ppm in the tank. It is when the nitrogen cycle comes to play, and it is the reason why cycling the tank becomes imperative. 

As soon as the ammonia levels rise, nitrifying bacteria, also called beneficial bacteria, start working. They settle on the filter and gravel of the tank and start eating ammonia. With this, the level of nitrite will increase. Nitrite is a by-product of the ammonia eating bacteria and is again very toxic to fish. Even at low levels, nitrite can be lethal, damage the fish permanently, and eventually make them die. This is the stage when the second colony of bacteria that have started forming by now will come to play. 

Nitrites will convert into less toxic nitrates by the second colony. Nitrates will remain in the water until you change the water and are the final product of the nitrogen cycle. Nitrates are beneficial to the plants as well, and they take them as a nutrient. 

Here you need to check the levels of ammonia and nitrites. If they have dropped to 0 ppm, your tank is cycled. Now, once you do the water change and bring the level of nitrate to less than 30 ppm, you can introduce the new fish. Your tank is not completely safe for them to survive. 

How to cycle an aquarium 

When you think about cycling the aquarium, the foremost thing you should do is testing the water with the help of a water testing kit. These test kits are readily available in the pet stores in the form of liquid testers and test strips. The readings from the kit will help you know the levels of different harmful chemicals. 

In the next step, you have to introduce ammonia in the tank that will trigger the growth of beneficial bacteria colonies. It can be done in different ways. 

Cycling the aquarium with fish

It is one of the most common ways that aquarists used to adopt to cycle the aquarium. When there are fish in the tank, they excrete, and their fecal material breaks down to release ammonia. Since ammonia is essential to commence the cycle, the process starts automatically. 

Although it is one of the feasible ways, it is also cruel and therefore not recommended. Secondly, it is a time taking method as well. You have to change the water frequently to keep the fish alive and to prevent their permanent damage. When fish are used to cycle the aquarium, the high amount of ammonia becomes fatal for them and causes their death. Pet store owners advocate the method as it helps them to earn more. 

Let’s take a look at cruelty-free and much easier ways to cycle the aquarium. 

Cycling the aquarium with food

As we have already told that uneaten and leftover food, when breaks down, converts into ammonia. And ammonia is all that we need to start the nitrogen cycle. Therefore, to cycle the tank with food, add a good amount of fish food inside it and leave it there to decay. 

Although this method is pretty easy, it is not completely risk-free. When the food rots, it not only releases ammonia but also becomes a nice dwelling place for the harmful bacteria. It makes the water very dirty. Therefore, whenever you cycle the tank with food, make sure replacing around 80 to 90 % of the water before introducing fish inside it. 

Cycling the aquarium with ammonia 

In this method, you have to buy pure household ammonia for cycling. It can be easily found in the garden stores or supermarkets where it is sold as a cleaning product. Small containers of ammonia are also found in the pet stores. 

Use one drop of ammonia per gallon of water. Keep the water testing kit near and test when the level of ammonia drops to zero. Repeat adding a drop again and wait until both ammonia and nitrite levels come to zero. As soon the reading comes out to be 0 ppm for both, your tank becomes fish ready. 

Before introducing the fish, change a large quantity of water and bring the level of nitrate to less than 30 ppm. If you are not adding the fish yet, keep on adding a drop of ammonia so that your beneficial bacteria do not starve to death. 

Seeding the filter 

You can find cycled filter media at pet stores. These filter media comprises beneficial bacteria colonies that make then tank fish-ready. It is one of the shortest ways of cycling the aquarium; however, there is a risk of disease and pest infestation through it. You can add fish instantly, but make sure the donor tank is completely disease-free. 

You can also find seeding material from a well-established tank or the pet store. You have to use the media as soon as possible. Moreover, while transporting, ensure that it comes in the same water of the tank from where you are bringing it. It should not be kept out or made sit for more than 1 hour to get the best result. 

If the media is sitting or taking more than an hour, it is advised to put an air stone into the bucket. It will provide all the beneficial bacteria along with oxygen and prevent them from dying. 

Bottled bacteria 

Another way of introducing a filter media is bringing them from a pet store where they are readily available. Please make sure you check its date of expiry. At the same time, always keep them in a cool and dark place to retain its value. Using an expired filter media will be no good to the tank as the beneficial bacteria might have died. 

Although bottled bacteria are highly useful, you cannot add fish right away. They are best to kick start the process of cycling and will also take lesser time than other methods. They work the best when combined with a water conditioner that removes the traces of nitrite and ammonia, making the water fish-friendly. 

Final words

Cycling your aquarium is as important as feeding your fish. Just like a poorly fed fish usually die, an unhealthy water ecosystem of the tank does the same. Therefore, cycling the aquarium to create a healthy environment is very important. 

If you want to escape the problems like the death of fish, stress among fish, constant water changes, etc. you need to keep an eye on the levels of ammonia and nitrite and keep them below the hazardous level. It will ensure your fish will remain healthy and happy. And at the same time, you will enjoy your hobby of fish-keeping.