Cycling describes the establishment of the nitrogen cycle in an aquaponic system by the colonization of nitrifying bacteria. Based on the preferred cycling method, this process may take months or weeks to complete. In this article, I will discuss the expected duration of aquaponics cycling and the different means of speeding it up without harming the system.
What is cycling in aquaponics?
Establishing a bacterial colony in new aquaponics systems is known as system cycling. This procedure entails continuously feeding the newly formed bacterial colony, establishing a biofilter, and adding an ammonia supply to the system. The fish may produce ammonia or be introduced in other ways. The nitrifying bacteria cannot start working or increase in numbers if ammonia is not present in the system.
Monitoring the nitrogen levels allows us to gauge the cycling's progress. Ammonia from decaying fish food and fish waste is converted into nutrients for plants by the nitrogen cycle. However, nitrifying bacteria need to be present for this process to happen. The plants consume the nitrates produced by these nitrifying bacteria after first converting ammonia to nitrites and then to nitrates. When the nitrate levels gradually rise and the ammonia level is less than one ppm, your new aquaponics system is deemed fully cycled. During testing, there is no nitrite present (zero ppm).
How does cycling work in aquaponics?
For aquaponics to take place, there are some considerations that you should know about:
- You must become familiar with the procedure for running water tests and understanding the results. Utilize a dependable water test kit because understanding the status of your water is crucial.
- If you employ the cycle with fish technique, think about employing a cheap fish as a sacrifice.
- Consider adding composting red worms to your grow bed once your system has completed its cycle.
There are two methods of performing system cycling in aquaponics. These are cycling with fish and without fish.
Cycling with fish
The traditional method of cycling new aquaponic systems takes 25 to 40 days and uses fish. Here are the steps to observe for this kind of cycling:
- Add a few fish to the tank to begin the fish cycle process. The reason for this is that too many fish will raise the ammonia levels and damage the fish.
- Once the fish are in, feed them sparingly to get the cycle going and waste production going.
- Each day, check the ammonia, nitrite, and nitrate levels to ensure they don't get too high. To prevent an ammonia spike, you must do a partial or complete water change if the ammonia level exceeds 3.0 ppm. Nitrite should be kept below 1.0 ppm, ammonia below 3.0 ppm, and nitrate levels should rise over time.
- Until your fish tank is completely cycled, keep an eye on the ammonia, nitrite, and nitrate levels and change the water as necessary. When your ammonia and nitrite levels stay below 0.25 ppm, your aquaponics system is fully cycled.
Cycling without fish
With a new aquaponics system, ammonia can be introduced without fish. You will experience less stress as a result, but the fish will benefit more in this situation.
If you consider fishless cycling, here are some excellent sources of ammonia to be used in the process:
- Liquid ammonia
- Ammonium chloride
- Dead fish
Here are the steps to take in performing fishless cycling:
- When your aquaponics system is ready, gradually add an ammonia solution to the fish tank until the ammonia test indicates a reading of -5 ppm.
- Keep track of how much ammonia it took to get to the -5 ppm level and add that much every day until the nitrite level reaches 0.5 ppm.
- Once nitrites form, reduce back the daily dose of ammonia to half of the original volume.
- Your system is fully cycled when nitrates reach 5 to 10 ppm and nitrites reach zero, at which point you can begin adding your preferred aquaponics fish.
How long does cycling in aquaponics usually take?
The traditional method of cycling new aquaponic systems takes 25 to 40 days and uses fish. The reason behind the long duration is that this technique causes the nitrifying bacteria to grow very slowly.
Fishless cycling is today's new aquaponics system's most often used cycling technique. While it takes a few days to one week, it has more excellent benefits than cycling with fish. The grower and the fish will experience less stress while cycling. Second, since no fish are involved in the process, rising ammonia, nitrite, and pH levels shouldn't cause undue anxiety.
How can you make an aquaponics system cycle faster?
One of the most challenging aspects of installing an aquaponics system is "cycling." Fortunately, there are methods to aid in accelerating the procedure. Here are some ideas to help you set up your system and get your plants growing more quickly:
Introduce bacteria from an established system
Here, I advise employing a filter or sludge from the grow media to quickly and successfully colonize a newly created system. However, since the disease can spread quickly between systems, it is crucial to ensure the borrowed bacterium is from a healthy system.
Use ammonia chloride:
The cycling process can be accelerated by employing ammonia compounds like ammonium chloride. But do add very modest amounts of ammonium chloride at a time.
The chemical can increase ammonia levels, which can cause fish deaths when added to fish. As a result, I advise using fishless cycling for this approach of accelerating things.
After each addition, the ammonia concentration should be monitored until it reaches 4 to 6 ppm. You can substantially speed up the process by incorporating an amount of water that nitrifying bacteria have already colonized.
Keep the temperature warm
Bacteria prefer warm environments and function best when temperatures are between 77 and 86 F (25-30 C). Therefore, the optimal time to cycle an aquaponic system is during the hot months or when summertime occurs.
As a precaution, it is inadvisable to cycle an aquaponic system in the winter or throughout the cooler months. If you must cycle during these hours, use heaters to keep the water at the proper temperature.
Maintain the pH at 6.8
The pH will first tend to rise as the amount of ammonia in the system increases. In such a situation, it is crucial to monitor the pH levels once cycling is finished. pH-lowering chemicals can be used to reduce the pH.
High oxygen conditions are ideal for the growth of bacteria. The rate of bacterial colony growth increases with the amount of oxygen in a system. In addition to promoting bacterial colonization, high oxygen levels keep your fish and plants healthy.