Is Aquaponics Right For You?

Aquaponics is a sustainable and environmentally friendly food production technique that merges two practices: aquaculture, which consists of cultivating aquatic animals such as fish, shrimp, crayfish, or prawns in tanks; and hydroponics, which involves growing plants in water. The system operates as a closed-loop ecosystem, utilizing nitrogen-fixing bacteria naturally present in the environment to convert waste products from the aquaculture system into nutrients for the hydroponic plants. This integrated approach eliminates the need to discard water or use chemical fertilizers, making it an eco-friendly solution.

A conventional aquaculture setup can accumulate animal waste byproducts (in the form of ammonia) that gradually become toxic to the cultivated animals. Consequently, every day, around 10 to 20% of the water must be drained and substituted. Nevertheless, in an aquaponic system, the water obtained from the aquaculture component of the system is streamed into the hydroponic component, where plants grow with their roots immersed in the effluent (waste) water. The ammonia contained in the effluent water is transmuted into nitrates and nitrites by bacteria, which plants uptake as nutrients. In essence, aquaponics is an integrated system that combines the benefits of aquaculture and hydroponics while resolving some of the problems associated with each of these systems.

Benefits of Aquaponic Systems

Waste nutrients produced by fish/aquatic animals are recovered by the plants. This eliminates the need to discharge water into the environment and minimizes the need to exchange water (other than topping off the water that evaporates and goes into the plant biomass). Compared to traditional aquaculture, aquaponic systems use much less water, which is especially attractive in arid, water-scarce regions of the country like New Mexico. As an example, an aquaponic system uses 1% of the water required in pond culture to produce equivalent yields of tilapia.
By minimizing the need to exchange water, overall operational costs are reduced. This is particularly important in arid climates like New Mexico, and in heated greenhouses where water or heated water can be a major expense.
Because of the daily application of fish feed to the system, the plants receive a steady stream of nutrients, which eliminates the need to discharge and replace depleted nutrient solutions, as would be the case in hydroponic systems.
Unlike hydroponic systems or recirculating aquaculture systems, aquaponic systems require substantially less water quality monitoring.
The same media used to grow the plants also serve as the surfaces on which the nitrogen-fixing bacteria grow. The plants being grown act as filters by removing the nutrients from the effluent water. This eliminates the need for separate biofilters, which can be expensive.
Plants grown in aquaponic systems receive most of their required nutrients at no cost, thereby improving the profit potential of the system.
Finally, by producing two crops (vegetables and fish) with the same system, the operational and infrastructural costs are shared, which increases the savings and profit margins.

Aquaponics enthusiasts have diverse objectives. Some focus on the plants they cultivate, using fish and aquatic animals as an affordable source of nutrients. Others rear both plants and fish for consumption or sale. Select growers breed edible fish, while others opt to produce ornamental varieties such as goldfish. As a locally sourced product, aquaponic systems are free from pesticides since their use would endanger the fish. Therefore, plants grown through aquaponics need minimal or no extra fertilizers.

Fish Suited to Aquaponics

Recirculating aquaculture systems are conducive for the growth of numerous warmwater and coldwater fish species. These consist of Arctic char, channel catfish, common carp, goldfish, largemouth and striped bass, perch, rainbow trout, and tilapia. Out of these, tilapia is the most commonly grown in both commercial and home-based aquaponic systems due to its ability to thrive in recirculating systems despite changes in water conditions and high densities. However, it is not indigenous to New Mexico, and hence, its or any other exotic non-native fish’s culture is regulated by the New Mexico Department of Game and Fish.

Things to Consider Before Starting an Aquaponics System

When preparing your aquaponics system, these are crucial aspects that you should take into account.

Personal Considerations

Select the type of aquaponics system you plan to use, which may include a media-based, raft, NFT, or hybrid system.

What are the goals and purpose of your aquaponics system?

To ensure that you achieve your objectives and aim, it is important to consider what you intend to grow and rear in your aquaponics system, as well as whether you plan to consume your fish. This will enable you to plan your system properly and determine the approach that suits your needs and aspirations.

Do you like to do-it-yourself (DIY)?

When it comes to planning your aquaponics system, deciding between building it yourself with DIY techniques or purchasing a pre-made system that’s ready to set up is an important choice to make. Which do you prefer?

Although DIY Aquaponics requires experimentation, it can result in an enjoyable and enriching educational journey. Nonetheless, opting for a pre-made aquaponics system can offer speedy operation and technical assistance.

Environmental Considerations

Humidity: In an aquaponics system, the water flow is constant, so you must consider your space’s natural evaporation and increased moisture.
Water Spillage: Your fish tank or aquarium can leak. Therefore, the area where you want to create your system is an area that can get wet.
Lighting: Plants need light to grow. All plants require sunlight for photosynthesis, which converts light, oxygen, and water into carbohydrates (energy). Plants need this energy to produce, bear fruit, and bloom.

In an aquaponics system, plants thrive best under natural light from the sun. However, if you have an indoor system, supplementing your plants’ light requirements with grow lights becomes necessary. It is crucial to carefully choose artificial lighting as plants absorb wavelengths beyond human perception at both ends of the light spectrum.

Location and Space Considerations

When selecting a location for your aquaponic system, there are several important factors to keep in mind.

Access to natural light: Plants require enough light to grow, so choose a location where natural light or sunshine is accessible.
Temperature: Choose a location where the temperature can easily be regulated. Consider installing a heater or air conditioner to maintain a consistent temperature.
Water source and drainage: Your aquaponic system will require a constant water supply, so choose a location near a reliable water source. Also, ensure that your location has adequate drainage to prevent water from accumulating around the system.
Electrical outlet: Your aquaponic system will require an electrical outlet to power the water and air pumps. So choose a location near an outlet or consider using an extension cord to reach a nearby outlet.
Ventilation: Proper ventilation is vital to prevent the buildup of humidity and to ensure that there is adequate airflow for the plants and fish.

Types of Aquaponics Systems

Aquaponic systems can mainly be classified into four types: media-based, raft systems, nutrient film techniques, and hybrid systems. Each category of systems has its own benefits and shortcomings. Hence, it is crucial to select the appropriate system that is suitable for your requirements and spatial limitations.

Media-Based Aquaponics System

Among the various aquaponics systems, the media-based system reigns supreme in terms of popularity. This system involves cultivating plants in a medium, like gravel or clay pellets, which serves as a substrate for beneficial bacteria to convert fish waste into essential nutrients. Consequently, the treated water finds its way back to the fish tank.

Raft System

The raft system of aquaponics, or Deep Water Culture (DWC), is a highly effective aquaponics design that is frequently employed in industrial or commercial settings due to its ability to produce large quantities.

The arrangement involves suspending the plants on rafts on the surface of the fish tank’s water, allowing their roots to dangle and benefit from the breakdown of fish waste by beneficial bacteria, which in turn supplies the plants with nutrients.

Nutrient Film Technique (NFT) System

The Nutrient Film Technique (NFT) is a hydroponic growing method that has been modified for use in aquaponics due to its uncomplicated yet efficient design that is suitable in certain settings. This process involves utilizing flat pipes (PVC) wherein nutrients are streamed in shallow waters. The NFT proves to be popular in commercial aquaponics and is also useful in metropolitan areas where food production and space limitations are major concerns.

Hybrid Aquaponics System

By combining various types of aquaponics systems, a hybrid aquaponics system is formed. A hybrid system is frequently employed in commercial aquaponics due to its efficient use of space. A mixture of raft and media-based systems is one example of a hybrid system.

Aquaponics Systems Materials

In order to establish an aquaponic system, there are a number of crucial materials that you will require. These include:

Fish -Fish provide waste that is converted by the beneficial bacteria into nutrients for the plants. Beginners should choose hardy fish species like tilapia and goldfish because they can survive under several water conditions.
Plants – Plants provide crops for your harvest and clean the water for the fish to live.
Fish tank – The fish tank provides a home for the fish, so it is important to choose a fish tank that is made of sturdy and safe material, like food-grade plastic or glass. Your fish tank’s size should be determined by the number and type of fish you plan to raise and the size of your system.
Grow bed – The grow bed is where your plants will grow. Ensure that your grow bed is durable and made of non-toxic materials. The size of your grow should be based on the size of your fish tank and the number and type of plants you plan to grow.
Plumbing system – The plumbing system circulates water from the fish tank to the grow bed and back. It includes a water pump, tubing, and fittings to create a continuous water flow. A siphon or overflow system can also be used to regulate the water level in the grow bed.
Water pump – The pump is responsible for circulating water from the fish tank to the grow bed. Select a water pump with a flow rate that can support the needs of your plants.
Air pump – An air pump is used to oxygenate the water in the fish tank.
Tubing and fittings -Tubing and fittings connect the various components, such as the water pump, air pump, and grow bed.
Grow media – Grow media provides a surface for beneficial bacteria to grow. Common grow media include gravel and expanded clay pellets.
Aerator and Air Stones – Are used in the fish tank and media beds.
Grow Lights – Optional. This is mainly used in indoor systems.
Heater – Optional. Using a water heater will depend on your location, fish species, and target water temperature.
Monitoring System – A monitoring system is an optional equipment that depends on your budget, and how you want to manage your system.
Timers and Controllers – are mainly used for lighting, pumping, and controlling the temperature.

These are the required materials:

Water Quality Test Kit
Cycling Kit
Fish Food
Fish Care Products
Gardening Supplies (gloves, pruning shears, sprayer, etc.)
Seeds and Seed Starting Supplies

Water and Nutrient Management

The health and productivity of your fish and plants is heavily reliant on maintaining a favorable nutrient balance and high water quality. It is therefore important to consistently ensure that your system’s water quality remains optimal in order to prevent any issues.

Cycling Your System

Establishing a healthy balance among fish, plants, and bacteria in your aquaponic system can be achieved by cycling it. Thus, it is crucial to let the required bacteria settle and initiate the decomposition of fish waste during the setup process.

Water Quality Management

When dealing with the water quality of your aquaponic system, there are certain factors that must be taken into account.

pH Levels: The pH levels should be maintained between 6.5 and 7.5 for optimal plant growth and fish health. Regularly test the water to ensure pH levels are within this range.
Ammonia Levels: Ammonia is present in the waste produced by fish. Excessive ammonia in the system can harm the health of the fish and plants. Monitor ammonia levels regularly and take action to reduce levels if they become too high.
Nitrate and Nitrite Levels: Nitrate and nitrite are necessary for plant growth. However, they can also be toxic to fish if levels become too high. So regularly monitor the nitrate and nitrite levels of your system and take action to reduce levels if necessary.

Nutrient Management

To achieve optimal plant health, it is important to maintain a balanced and adequate nutrient level in your system. Below are some elements to contemplate when managing nutrients in your system.

Understanding Nutrients: The three main nutrients that plants in aquaponics systems require for growth are nitrogen, phosphorus, and potassium. These nutrients should be found in fish waste and should be supplemented if needed.
Testing Nutrient Levels: Regularly test nutrient levels in your system using a nutrient test kit. This will help you determine if nutrient levels are balanced and sufficient for plant growth.
Supplementing Nutrients: If nutrient levels are too low or certain nutrients are deficient, it may be necessary to supplement with additional nutrients so your plants will grow healthy and bear many flowers and fruits. This can be done using a variety of commercial nutrient supplements or natural methods, such as adding compost or worm castings to the system.