Aquaponic farming is a farming technique that combines hydroponics (using nutrient solutions to grow plants) and aqua-culture (fish farming). Through aquaponic farming, you can use limited space and other resources to grow organic food in a self-sustainable garden.
Through this farming technique, you can make use of beneficial bacteria to raise fish and grow plants. These two components operate in tandem, allowing you to develop an effective farming system.
How Does Aquaponic Farming Work?
In aquaponic farming, you grow plants on the growing bed while the fish are placed inside a tank. The water present in the tank (containing fish waste) travels to the growing bed, where the millions of natural, beneficial bacteria work to break down the ammonia into nitrites and eventually nitrates.
These nitrates, along with other nutrients, support the plant growth. In return, these plants filter and clean the water, and this oxygenated and fresh water then goes back to the tank – reinitiating the whole cycle.
Types of Aquaponics Systems:
Below, we discuss the four main types of aquaponics systems:
Media-Based:
This kind of system is also known as ‘Food and Drain’ system. The media based aquaponics system is by far the most common of the four, and is used in commercial farms and backyard systems.
This system uses a grow container or bed consisting of grow media (such as clay pebbles, rock, or lava). The grow media is used for planting the crops, and a bell siphon is used to periodically transfer water from the fish tank towards the growing bed. This water then returns to the fish tank, marking the completion of one cycle.
The grow bed breaks down all the waste – sometimes, worms might be added to the bed in order to facilitate the waste breakdown. The media-based aquaponics system requires few components and no extra filtration, which makes this method quite easy to execute. However, since the growing space is limited, the produce in this system is relatively lower.
Raft System:
The second kind of system is the raft system, also known as Floating System or Deep Water Culture.
In this system, long canals (with depths of approximately 20 centimeters) are used to transfer the nutritious water, while rafts (foam board or polystyrene) float atop. The raft boards are used to grow the plants. The roots of the plant soak up the oxygenated and nutrition-rich water, which allows for rapid growth. The filtration process allows this water to flow constantly from the fish tank, and then towards the raft tank to help the plants grow. Finally, this water returns to the tank, marking the end of one cycle. Generally, the raft tank and fish tank are kept separate.
Nutrient Film Technique:
The Nutrient Film Technique (NFT) involves the use of narrow and long channels to grow plants. NFT was initially a hydroponics technique but, owing to its simplicity and effectiveness, has been adapted for aquaponic farming.
Like we mentioned, the NFT method uses long and narrow channels to grow plants. Thin films of water constantly flow down every channel, providing plants with the oxygen and nutrients that they need in order to grow. Similar to the raft system discussed above, the water travels moves from the fish tank using filtration components, and makes its way to the plant-growing NFT channels, and then returns to the fish tank, marking the completion of one cycle. Since there is insufficient surface area for the useful bacteria to reside, the NFT method requires the use of a separate bio-filter.
Hybrid:
As the name suggests, the hybrid system combines multiple aquaponic system types. Many commercial aquaponics setups – and even some home growers – make use of hybrid systems, since they allow for greater efficiency and better utilization of space.
The hybrid aquaponics system involves several approaches, any of which can be beneficial depending upon the specific design. An example of the hybrid system is an amalgamation of the media-based and raft systems.
Factors to Consider when Choosing an Aquaponics System:
Below are some of the factors that you need to focus on when selecting an aquaponics system:
Purpose:
Are you looking to simply experiment with this system? Do you want to grow your own food, or are you planning to establish a commercial setup? Knowing your purpose behind aquaponic farming will help you pick the system that best suits that purpose.
Crop Type and Size:
The size of your aquaponic system will determine the size of your plants. A smaller system will support smaller species of plants (herbs and leafy greens, for example). Meanwhile, larger systems can be used to grow larger plants or even fruit trees.
Budget:
Of course, the amount of money you are willing to spend on an aquaponic setup will play a crucial role in determining the right system for you. Your budget will also determine the type of labor, equipment, and plants needed for the system.
Benefits of Aquaponic Farming:
Aquaponic farming is a good choice for anyone wanting to sustainably grow and consume organic food. You can set this system up indoors, in your backyard, or even in controlled environments like greenhouses. Using a controlled environment means that you will be able to grow almost all kinds of foods throughout the year, regardless of season.
Although starting a major aquaponic farm will require large investments (like pre-manufactured aquaponics kits), you can even pull it off in a budget-friendly manner by using recyclable materials and employing DIY techniques.
Below are some of the benefits of using aquaponic farming:
- Allows you to grow food throughout the year by using greenhouses or managing your growing requirements.
- Compared to conventional farming, aquaponics farms uses almost 70% less water. Since the water in an aquaponics system is constantly recycled, there is no need to discard or change it.
- Aquaponics does not use soil, which means that you do not have to worry about your garden being lined by weeds. As a result, you will have more time to focus on and enjoy the actual farming process.
- Since plants get 24-hour access to nutrient-rich water, they grow faster and better with aquaponics.
- If you go commercial, an aquaponics system can serve as an additional source of income for you and your family.
- Growing your own food means that you do not have to worry about what you are putting into your body.
- Aquaponics is usually inexpensive to install, and does not require large amounts of land.
- With aquaponic farming, you do not need to use harmful fertilizers or chemicals.
Which Fishes to Use in Your Aquaponics System?
There are many different kinds of fishes that can be suitable for an aquaponics system, such as:
- Tilapia: This fish is easy to care-for and grow, and it is quite resistant to disease.
- Goldfish: Goldfishes are a good option, since they produce a great deal of waste that can be beneficial for your plants.
- Koi: The Koi fish has a good resale value, and grows to become quite large.
- Pacu: If you want a fancier type of fish.
- Carp: Easy to care-for and grow, and reproduce well.
- Silver Perch: A school fish that grows fast and enjoys high densities.
- Catfish: The absence of scales means that handling must be minimized.
- Barramundi: This is perhaps the uncrowned king in the world of aquaponic fishes.
Which Plants to Grow in an Aquaponics System:
Like we mentioned, most aquaponic setups tend to support the growth of leafy plants. However, considering that you have sufficient fish, you can even grow fruiting plants like tomatoes and peppers.
Below are a few simple-to-grow plant choices for your aquaponics system:
- Basil
- Kale
- Watercress
- Mint
- Lettuce
If you have an established setup and a decent fish population, you could also consider growing the following plants:
- Tomatoes
- Peppers
- Beans
- Cauliflowers
- Cabbages
- Squash
- Cucumbers
- Strawberries
- Peas
Regardless of the plant(s) that you choose, make sure to place the plant roots gently in the pebbles; it is important that the roots are deep enough to be able to absorb the nutrients from the water.
Final Word
The right components can help you create the perfect aquaponic farming system according to your needs and objectives. The more comprehensive and detailed your planning is, the easier the actual execution is likely to be. We hope that this guide helped you with the ABCs of aquaponic farming, and will prove to be a useful resource as you implement and benefit from this game-changing farming technique. To learn more about aquaponic farming, please feel free to check out some of the other blogs on our website.
