How to Nitrogen Cycle your Aquarium

feed fish

Aquarium cycling is the process of getting rid of toxins that accumulate in aquarium water, the process is also known as the nitrogen cycle.

Therefore, when you cycle your aquarium you are creating a bacteria bed the will obliterate the toxins. Aquarium cycling can take up to 4 weeks, and after you finish you can then test it to ensure that ammonia and nitrite are no longer present, it will then be safe to introduce new fish into the tank. 

Cycling processes are two, one involves cycling with the fish in the tank and the other process fish are normally not present. With the latter, you will have to create an environment that will lead to the generation of ammonia, such as putting fish food into the tank and leaving it inside so that it can disintegrate and produce ammonia. 

Aquarium cycling with fish 

Not all types of fish can survive during the cycling process, some are hardy and will make it through the entire process, while others will most likely get diseases and die before you finish. If you plan to use the fish cycling method then do thorough research on the types of hardy fish that will go through the process and come out successful. 

1. Introduction of fish 

The reason for introducing fish is because we want to ensure that there is enough waste produced by the fish. You will, therefore, add either one or two fishes in every 10 gallons of water, but don’t add a lot of fish in a bid to quicken the process, because you will inadvertently kill the fish as the levels of ammonia will have spiked. 

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The best types of fish for the process are such as the Minnows, the Zebra Danios, the Pupfish, the white clouds, the banded Gourmis and the Cherry or Tiger Barbs. The list is not conclusive as there are many other types of hardy fish apart from the mentioned that you can use in your aquarium. 

2. Feeding the fish  

feed fish

You will then have to feed your fish but make sure that you don’t overfeed them as you might think that feeding them a lot of food will enhance the cycling process. It is true the waste will be produced in large quantities but the problem is that the good bacteria will not have been produced in time to take over your aquarium. 

Also, feed them food that they can consume in a short time because the remaining food particles in the water will rot and disintegrate and end up producing more toxins 

3. Changing the water 

The benefits of changing water is to moderate the level of toxins and make sure that they don’t become too high for the fish to handle. You will, therefore, change the water at least after every 2 or 3 days, if you exceed that then you risk obliterating the developing ammonia and nitrite that is supposed to be food for the beneficial bacteria,  and don’t forget to add a de-chlorinator. 

4. Test for the levels of toxin 

water tester

The fourth process involves using a test kit to test for the levels of ammonia and nitrite, remember as you start the process nitrite is normally not present but develops a few days later, and the reason why you should check if it is developing or not. 

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Testing of ammonia is not very wise because of the very toxic levels, but you also need to keep track of its levels so that you can manage the fish and ensure that they stay safe. Remember when the level of nitrites begins to drop it is an indication that the process is almost complete. 

5. Add fish 

Once you establish that the levels of the toxins have dropped to zero then you can now start adding other fish, don’t dump a lot of fish into the aquarium but rather introduce them gradually while testing to see the levels of toxins. If the levels of ammonia and nitrite have not spiked then you can keep adding the fish. 

The fishless cycle

1. Introduce fish food

If you recall from the previous process we had fish that was responsible for the production of waste that would later disintegrate and form ammonia. You will, therefore, drop into the water a few pieces of fish food, such as the fish flakes and wait for them to rot so that they can release ammonia. 

2. Test to check for ammonia 

An ammonia test kit will be handy to help you keep the levels of ammonia in check, ensure that they are about 3 ppm (3 parts per million). If it is below the recommended then you will have to add more fish food so that it can increase the level of ammonia produced. Nitrosomonas bacteria will then begin to grow and start consuming the ammonia. 

3. Test for the presence of Nitrites

Nitrites can be tested using a commercial kit; the presence of nitrites in the water is an indication that the cycle has started but that should not stop you from adding ammonia. 

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4. Test for the presence of nitrates

After weeks of testing for nitrites and ammonia then the levels of nitrites will begin to drop, this is, therefore, the right time to begin testing for nitrates. When you detect nitrates in the water then you know that the cycling process is over. 

Ammonia and nitrite level will at this point go back to zero, however, the levels of nitrates in the water shouldn’t be too high and in case they go beyond 40 then it might be good to change the water to dilute the high levels. 

Introduce new fish

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The absence of ammonia and nitrite means you are free to add fish, and just like the previous process this you will do gradually. However, you could also clean the substrate before you proceed to add any type of fish, just to get rid of any chances of ammonia developing because of some forgotten leftover disintegrated fish food. 

Lastly, as you engage the cycling process check to ensure that your aquarium actually begins the cycling process, as it is very possible for it to fail to start cycling, the ammonia levels could also fail to drop and that the nitrates levels fail to rise. In the latter case, it could be because of using chlorinated water or too much tank cleaning.

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