Practicing aquaponics could be challenging to experienced and newbies since there are specific skills that one must be acquainted with for the system to become successful. Yet, these can be mastered through continuous practice. Also, the World Wide Web serves as a repository of valuable materials on how you can successfully set up, sustain, and scale-up any aquaponics system you will adopt.
What is aquaponics?
The growing of plants and aquatic animals in a recirculating environment is known as aquaponics. It is a combination of fish and plants production. The term comes from aquaculture (fish farming in a controlled environment) and hydroponics (growing plants in a soil-less environment). Aquaponic systems are available in various sizes, ranging from small domestic units to massive commercial systems.
Aquaponics systems can produce healthful foods (fish, herbs, fruits, and vegetables) in high yields by recycling the water, contributing to food and nutrition security while also being a profitable commercial endeavor suitable for developing and developed countries.
Aquaponics is a low-tech, controlled food production method that employs fewer than 10% of the water needed for traditional fish farming and plant agriculture. As a result, it is ideal for both small-scale/domestic consumption and commercial fresh food production, especially in water-scarce regions. There is very little water loss, primarily due to evaporation and plant transpiration; there is also no need for plant chemicals, which would kill the fish; however, some organic plant protection may be required, mainly if monoculture is grown.
How does aquaponics work?
Aquaponics is a hybrid of aquaculture (the cultivation of fish and other aquatic creatures) and hydroponics (the cultivation of plants without soil). Aquaponics combines the two via a symbiotic relationship in which plants are fed by the discharge or waste of aquatic animals. In exchange, the veggies help clean the water returned to the fish. In addition to fish and their excrement, microbes play a significant part in plant nutrition. These beneficial bacteria colonize the gaps between the plant's roots and convert fish waste and sediments into nutrients that the plants may use to thrive. The result is a seamless integration of aquaculture and gardening.
For an aquaponics to operate at its optimum, the following components must be present:
These components are necessary for fish culture and should be large enough to accommodate the fish's growth. The fish must be comfortable and stress-free in the tank for the system to function correctly. Fish tank criteria can include whether the container is new or used, the manufacturing material, and the tank's size and design. It's frequently more cost-effective to employ a recycled tank in an aquaponics system; nonetheless, understanding the tank's history is crucial. IBC totes, for example, are accessible from liquid cargo transporters; however, if the equipment was originally used to hold dangerous chemicals or other substances that could harm fish, it should be discarded or reused.
Another crucial component of a successful aquaponics setup is filtration. This process is needed for solids removal (mechanical), and bacterial conversion (biological) of waste products created by fish into essential nutrients plants require for growth.
The primary goal of mechanical filtration is to filter and remove all visible particulates from the water column. Fish feces, uneaten feed, suspended bacterial colonies, and other inorganic substances are all examples of solids in the water column.
Solids are removed from the system as soon as possible by settling, as they put additional strain on the filtration unit. If solids are present in the design, they are broken down by heterotrophic bacteria. As the bacteria decompose the particles, they absorb dissolved oxygen from the system and produce ammonia. Increased ammonia concentrations combined with less dissolved oxygen in the water force the beneficial nitrifying bacteria community to work harder to convert ammonia to nitrate. Plants can absorb nitrate more quickly than other forms of nitrogen.
Water movement and aeration
Water flow is critical in any aquaponics system, especially in transporting waste to the filtration device and nutrient-rich water to the plant system. To achieve this scenario, you should purchase an appropriately sized water pump that meets this condition for water circulation. Submersible pumps are intended to be submerged within the fish tank and are frequently utilized in smaller systems where plumbing knowledge is not required. Purchase and use a submersible pump rated for continuous usage to extend the pump's life. External to the tank, an inline pump is piped inline within the system. These pumps are slightly more challenging to install, but they are relatively efficient in moving water across the system.
What are the different designs in aquaponics?
There are three major designs in aquaponics that are available for aspiring aquaponics practitioners:
This first type, also known as Flood and Drain, is widespread in small-scale aquaponics systems and is popular among do-it-yourself aquaponics home growers. The media-based system design is space-efficient and straightforward, with a cheap initial cost ideal for aquaponics beginners.
The media-based system comprises a grow bed filled with grow media (expanded clay pebbles, gravel, and lava rock) and into which the vegetables are sown. The water from the fish tank is pumped or gravity-fed into the grow beds, allowing the plants to consume the nutrients. The nitrifying bacteria colony is housed in the grow beds, serving as a growing environment for the plants. Some media-based aquaponics systems are operated by flooding and draining the grow beds, with the water being drained via a bell siphon when it reaches saturation.
Because of its mass-production capabilities, this system is frequently employed in large-scale or commercial aquaponics systems.
A raft system, another label for the deep-water system, circulates nutrient-rich water through long canals at a depth of about 20 cm, with rafts (polystyrene or foam board) floating on top. Plants are planted on raft boards supported by net pots within holes. Plant roots dangle in nutrient-rich, oxygenated water, absorbing oxygen and nutrients in order to grow quickly. The nutrient-rich water flows continually from the fish tank to the raft tank, where the plants are cultivated, then back to the fish tank. The raft tank and the fish tank are usually kept separate.
Nutrient Film Technique
Because of its simple yet effective design that works well in specific settings, the nutrient film technique, or NFT, is a hydroponic growing technique suited to aquaponics. This approach employs horizontal PVC pipes that carry shallow streams of nutrient-rich water. The NFT is widely used in commercial aquaponics and urban areas with limited space and food production.
What skills should I possess to practice aquaponics?
Aquaponics requires its users to exercise a particular set of skills that are vital for its success. Seasoned farmers may use their stocked knowledge in setting up and sustaining whatever aquaponics technique they prefer. On the other hand, those new in the industry can equip themselves with these skills for them to sustain, even scale up, their chosen aquaponics setups.
Apparently, these will equip you in maintaining the plants you choose to grow. The fundamental skills you need for growing productive plants include:
- Understanding the plant: Here, you should always check for the plants' leaves, stems, and roots, for they can help you discern the well-being of your growth.
- Choosing the suitable growing medium: In aquaponics, growth media serves as a substitute for soil. Many different materials are available for aquaponics, as long as they supply O2, water, and nutrients to the roots.
- Identifying essential plant nutrients: The nutrients that plants require are dissolved in water and delivered daily. Plants require large amounts of macroelements (N, P, K, S, and Ca) but only modest amounts of microelements (Fe; Zn; Mn; Mg; Cu; Co, Mg).
- Selecting the appropriate plant variety: Almost any plant can be cultivated in an aquaponic system. Distinct plants, on the other hand, have different requirements and grow in different environments.
- Safe pest and disease control: Plants in aquaponics are susceptible to specific diseases and pests. However, you can use techniques that will not harm the environment to control them. These are companion planting, weed mats, manual removal, etc.
- Proper harvesting practices: Vegetables and fruits are perishable, so it is imperative to observe harvesting practices that will prolong their shelf life.
Fish culture skills
Caring for your preferred fish variety is the ultimate goal of acquiring these skills. Let me share with you some aquaculture practices you should be familiar with:
- Fish selection: Fish growers can cultivate various species in a closed system. You can keep a large variety of fish in your aquaponics tank. It is always a good idea to look into the best fish for aquaponics accessible in your location, considering weather conditions and legality.
- Fish feeding: One of the most significant inputs in an aquaponic system is fish feed. The feed that goes into the system and the growth of your plants are inextricably linked. It is a standard recommendation to feed the fish only as much as they ingest in 5 minutes. Then, scoop out any leftovers to avoid water quality problems.
- Fish stocking: According to the Food and Agriculture Organization (FAO), the maximum stocking density of 20 kg per 1000 liters is used to determine the recommended fish density. Higher densities can be achieved with more aeration and mechanical filtering, although this is not suggested for novices. https://www.fao.org/3/ca4027en/ca4027en.pdf)
- Fish water requirements: In maintaining your fish, always observe the level of dissolved oxygen as well as the pH range. Not meeting the required levels will harm your fish' health and even your plants' growth.
The goal was to design and develop a sustainable aquaponics system based on water recirculation to support fish and plant culture (without soil usage). The system should monitor and adjust the essential system parameters to maintain the best conditions for both fish and plants. Due to this fact, any aquaponics practitioner should have a good grasp of basic carpentry skills.
Aquaponics is gaining a lot of practitioners today since it is a revolutionary and sustainable approach to food production. You are probably an aspiring aquaponics user, and the information from this article should give you an idea regarding what this recirculating system would require from you. Aquaponics might pose some degree of difficulty, yet it is a rewarding endeavor that you can apply to any open space.