In recent years, aquaponics has gained popularity, particularly among people who are enthusiastic about sustainable agriculture. The idea of combining hydroponics and aquaculture is brilliant, but one crucial component that makes the system work is biofilters. This article will explore biofilters in detail, including what they are, why aquaponics need them, and how to utilise them in your system.
What are Biofilters?
In simple terms, biofilters are living organisms that have the ability to remove or filter pollutants or contaminants from the water in a system. In an aquaponics system, inorganic substrates such as gravel serve as a refuge for advantageous microorganisms, enabling them to thrive and proliferate for the benefit of the system as a whole. When used correctly, biofilters will provide the correct temperature, pH, light, and nutrient levels required by these living organisms.
Why are Biofilters Important?
In aquaponics, toxic nutrient accumulation from fish waste and added elements like fish food mean the water needs to be constantly siphoned off and replaced with a clean supply. This is where biofilters come in. They convert the toxicities into plant-usable nutrients, thereby cleaning the water and making it fish-friendly once more.
How do Biofilters Work?
When pumped from the fish tanks into the grow beds, the water is highly concentrated with toxic ammonia. Nitrogen forms a big chunk of the ammonia complex, which is where the importance of the nitrogen cycle comes in. In nature, the nitrogen cycle is pivotal in converting atmospheric nitrogen into plant-usable forms. In aquaponics, we exploit this nitrogen cycle to convert toxic fish waste into non-toxic recycled water.
Two classes of microorganisms known as Nitrosomonas and Nitrobacter play pivotal roles in converting ammonia into plant-usable forms, thereby eliminating the toxic nitrogen sources from the water. Ammonia is changed into nitrites by Nitrosomonas, which are considerably more hazardous to fish than ammonia. In contrast, Nitrobacter converts the nitrites into nitrates. Plants may access nitrogen when it is in the nitrate state. At the last stage of the procedure, the plants remove the nitrates from the water, restoring their suitability for fish.
How to Use Biofilters in Aquaponics
If you have a media-based grow bed in your hydroponic system, you may not need additional filtering systems. However, if you are incorporating traditional hydroponic systems like the nutrient film technique or deep water culture into your aquaponics setup, you will need to think about adding biofilters.
If you are thinking of adding one to your system, you should install the biofilters between the fish tank and the plant system so the ammonia can be converted to nitrates before it reaches the plants. You also need to consider factors such as aeration and prior filtration of solid material.
Nitrosomonas and Nitrobacter are aerobic organisms, which means they need oxygen to survive. You must, therefore, make sure your system is adequately aerated. Venturi siphons or air stones can be included in your setup to ensure the water has sufficient levels of oxygen.
Biofilters are crucial components of any aquaponics system. They help to convert toxic fish waste into non-toxic recycled water, making it suitable for both fish and plants. By maximizing the surface area of your biofilters and providing sufficient levels of aeration, you can ensure that your system is efficient at detoxifying the water.