Aquaponics, as the name suggests is the combination of aquaculture and hydroponics.
What is aquaculture?
It is the production and maintenance of aquatic life that include both marine and freshwater organisms like catfish, salmon, scallops and oysters etc.
There are more than 100 species of aqua organisms at different stages of their life produced through aquaculture. The main requirement for aquaculture is clean and oxygenated water.
What is Hydroponics?
Hydroponics is the method of growing plants in water without soil. It is generally believed that plants cannot grow without soil. In reality it is the minerals and nutrients in the soil that are needed for plant growth and not the soil.
Water used for hydroponics is enriched with nutrients needed for plant growth. Plants absorb the nutrients dissolved in the water. All types of terrestrial plants can be grown in this method.
What is the Need For Aquaponics?
Aquaponics, a combination of both these systems is a system of raising aqua organisms and cultivating plants together.
In aquaculture the water may get polluted with toxins. The toxins must be removed and should be replaced with fresh water to avoid the aqua life getting affected by toxins.
In hydroponics system of plant cultivation, it is the nutrients that play an important role in plant growth. Enriching the water with all necessary nutrients can be an expensive affair.
The waste and the toxins from the aquaculture can play the role of nutrients for hydroponics. The nutrient rich water disposed from aqua culture sets the right platform for the plants to grow. Aquaponics is needed because it turns the minuses of aquaculture and hydroponics into pluses and the pluses of both systems are retained.
The method of growing crops and fish together in a recirculation system is surely needed to reap all the benefits and get rid of the disadvantages.
Starting an Aquaponics System
This is the first step in aquaponics. The system consists of two main parts namely the aquaculture to raise aqua animals and hydroponics to grow plants.
There are different ways to start a system.
Here is a simple technique. Fish is raised in a large water tank. The best choices of fish are fish that are easy to raise. The best examples are fish like Tilapia and yellow perch etc. Water from the fish tank is drained from fish tanks and transferred to a gravel bed which contains good bacteria.
Fish waste contains toxic ammonia that can be harmful to the plants. The good bacteria in the gravel bed convert the toxic ammonia into nitrogen. It is a well known fact that nitrogen is the primary requirement for plant growth.
In this system plants are grown in raised beds. Water is transferred to these raised beds. You need pumps and electricity to transfer water from gravel beds to the plant beds. In these beds you can grow vegetables and greens etc.
The plants make use of the nitrogen and other nutrients from the water and then the water flows back to the fish tank. Both water and nutrients are not wasted. You can sell both the fish and the vegetables.
This technique can be followed even if you have a very small backyard. It is not possible to grow commercial fish in this system. You can grow ornamental fish like gold fish etc. There are a few things for this technique.
First you need a bed to grow your plants. You can use anything if it is 300 mm if depth and if it is clean without any harmful chemicals. It can be a cement tank or a wide mud pot or a plastic barrel sliced into half. The bed should be filled with gravel. The seeds are spread into the tank. The seeds get placed in the spaces found in between gravels.
The next thing you need is a fish pond. Again you can use anything from a half drum to a fish tank or just a garden tank.
Then you need a submersible pool pump, electricity and two pipes.
The system works by flooding and draining method. The pool pump should be switched on every 15 minutes. When it is switched on the nutrient rich water flows from the fish tank to the plant bed. When it is switched off it is drained into the fish pond.
You can plant vegetables, greens and ornamental plants. You can slowly add more plants when you gain experience and taste success.
There are two main types of systems.
1, Media filled beds
In this system the plant beds are filled with media like clay, rocks, coir or anything similar. The water from the fish pond keeps on flowing to the grow bed in constant flow system and water keeps on flowing and draining in the ebb and flow method.
2. Deep water culture
In this system there is no need to fill any media. Plants are let to float over the water and the roots are let to hang underneath. Plants can be grown on a foam raft on the top of a fish pond. The floating plants absorb the nutrients from the pond.
There is another method. They can be grown in separate tanks allowing the water to be pumped, filtered and drained.
Types of filters for Aquaponics
Filtering is very important for aquaponics. There are many types of filters that are discussed below.
- Nitrification filter
In this method air is injected through the filtration medium from the bottom. This helps in conversion of waste into nutrients and oxygenating the water.
- Swirl filter
In this method hydrocyclone principle is used to let the large particles settle at the bottom.
- Sieve filters
They are commonly used. You can choose filters to suit your budget and needs. Inexpensive plastic filters are uses in homes. If you want to go for commercial use you can go for expensive options like stainless steel filters that are durable and strong.
- Mat filters
Foam pads are used to trap the waste particles.
- Brush filters
This is suitable for barrel system. Brushes are left to hang on the sides of the barrel and it collects the waste matters.
In this system, huge particles are allowed to settle at the bottom by reducing the velocity of water flow.There are other filters like bio filters, trickling bio filters and radial flow filters etc. Bio filters are preferable than chemical filters.
Cycling is as important as filtering because without cycling the waste cannot be converted into nutrients needed by plants. There are many varieties of cycling too.
Types of cycling
Urea fertilizers used for agriculture purposes can be used to cycle the water. If you add urea you should keep on monitoring the pH balance and other features of water regularly. You should be very careful with the dosage. Over dosage may cause undesired side effects.
Ammonia should also be added with care giving consideration to the dosage. You should make sure that the ammonia you add does not contain any artificial smelling agents and other chemicals.
- Fish feed
This is a good method of cycling because the chances of side effects are lower. Fish feed is dropped into the pond. It breaks down in the bottom of the beds and breaks into ammonia.
- Feeder fish
This is the best for commercial purposes. Add cheap feeder fish that includes guppies and comets etc. This is to be done in the initial stages when you install the system. It can be done for the first 2-3 months.
- Dead fish
Adding dead and rotting matter is one of the methods to introduce ammonia into the pond.
Selecting the system, filters and cycling
You should select the system depending upon the space availability, purpose and many more. If it is for commercial use or in a hotel or office with huge space availability you have to go for deep water culture. If it is for your backyard you can go for small and simple systems. Flooding and draining systems are easy to maintain and use.
The same policy apples for choosing the type of filtering and cycling.
The next important step is to select the type of fish and the types of plants.
Growing fish in aquaponics is easier than maintaining an aquarium, but you should be very careful about choosing the right fish and following the right steps in growing them.
Choosing the fish
Choosing the fish is determined by many factors. The factors to be considered are the local climate, available species in the local market, size of the pond, budget and purpose. The fish you choose should grow well in your climate. some of the fish survive in warm weather and some in cold weather. You can also go for fish that thrive in all types of climates.
You should also make sure that your local market has stock of the fish all around the year.
If you have huge space you can grow edible fish. If not you can grow ornamental fish. You can market both edible and ornamental fish. Decide which has a huge market and which is suitable for your system.
Fish species suitable for aquaponics include carp, goldfish, koi, jade perch, cod, trout, tilapia and baramundi, fresh water mussels, fresh water prawns and crayfish etc.
There are more than 300 species of plants that can be grown in aquaponics. Root vegetables, herbs and green leafy vegetables are the best choices. Vegetables like broccoli, cabbage, cauliflower, beets, cucumber, potatoes, sweet potatoes, tomatoes, greens and spinach grow well in aquaponic system. Dwarf fruit trees also are suitable for aquaponics.
The plant you choose should grow well in your climate. If it is for your own personal use you should grow your favorites. If it was for commercial purposes you should make sure that it has a good demand. You can also go for ornamental plants if you are interested in beautifying your backyard.
What are the Benefits of Aquaponics?
- It can be done anywhere you like. It is suitable in small and large spaces. You don’t need large cultivable lands to grow plants.
- There are no artificial fertilizers used. So the vegetables and fruits grown are bigger and healthier.
- Water from the fish pond is not wasted.
- There is no need to install a cleaning system for the fish pond.
- The edible fish grown is tastier and healthier.
- Growing plants in a garden or in the backyard is an interesting hobby. The biggest problem about this is the cleaning of debris, weeding and control of pests. All these problems are eradicated in aquaponics.
- There is no need to add fertilizers. Organic fertilizers are expensive and chemical fertilizers affect the vegetables and fruits cultivated.
- Choosing the right soil can be a challenging task. There is no need to add soil and you are relieved from the task of choosing the soil and keeping it fertile.
- Save water and save energy is the need of the hour. Both these targets are attained through aquaponics.
- You can save money because it is not very expensive. You are able to grow both plants and fish in one common system.
- It is suitable in tourist spots. It attracts huge crowds because it attracts people of all ages.
The only disadvantage of aquaponics is that you need to increase your knowledge on many new things. You have to choose the right system, cycling and filtering. You should have patience in the initial stages. You cannot expect to get success immediately. If you are interested in DIY and if you are ready to take risks and if you have enough time to spare you can do it yourself.
If you don’t have time and f you are really interested in Aquaponics you can get the help of professionals and companies who give you guidance and who help you to start and maintain aquaponics system in your home, hotel and schools etc. and for commercial purposes.
You are relieved from a lot of headaches. You need not worry about choosing the right equipment. They are sure to guide you in all possible ways. Make sure you select the right company that offers the best service at affordable rates.