Dear friends, clients, partners and aquaponic fans,
we wish to all a peaceful Christmas and a Happy New Year 2018.
Thank you for the year 2017 and we look forward to our future cooperation!
After all the years of hard work, we can say „ we did it “.
New products, new web, new vision, but it’s still us, THORILEX.
We’d like to thank our current and future customers for believing in us
What is aquaponics?
Have you heard about aquaponics and are you interested what is the purpose of this agriculture changing system? Which vegetables can be grown in aquaponics and which fish to breed in tanks? What is needed to run aquaponics?
Aquaponics is a combination of breeding fish and growing vegetables or fruits in a recirculating system. Fish excrements are turned into nutrients, which plants can absorb as a food, the clear water is then returned to a fish tanks. This way it is possible to breed many kinds of fish and grow large scale of vegetables, herbs and even fruit. Water consumption is minimal compared to growing in soil medium and nearby environment isn’t polluted by a water from fish breeding, that would have to be changed regularly. System like this is an ideal in locations where is not enough ground or bad conditions for the classical agriculture methods or hard access to clean soil and water.
An aquaponic system is made out of three parts, which can’t operate without each other. Fish food – commercial fish granule, ecological feed, but also processed kitchen waste serves as basic food for bred fish. They’ll use part of it to grow, however their imperfect digestive system excludes lots of nutrients back into the water. The substances are not available for the plants yet, but the substances are eaten by bacteria and other microorganisms and are changed into basic substances. Plants can absorb those basic substances through the roots and use them to grow or create fruits. This clears the water at the same time, so it goes back to the tanks. This cycle works naturally in every pond and is cleverly used in aquaponics to grow foodstuffs. In aquaponics it is also called Closed-loop System.
Breeding fish creates a lot of waste. But that can be used to grow plants. The Cycle begins with feeding fish and is very similar to nutrient flow in the nature. Fish can be decorative for example Koi Carp. Tilapia is the most common consuming type but also many kinds of carps, salmonidae or percidae fish. Fish are bred in big tanks, which should meet requirements for good water circulation. More about tanks in part Systems Types.
Fish waste is decomposed by helpful bacteria and other microorganisms to simple nutrients suitable for plant growing. In aquaponics there are two the most important processes that are handled by helpful bacteria. It is nitrification and mineralization. More about them can be found in part Biology and chemistry. The process of changing nutrients couldn’t work without the bacteria. You can’t use antibiotics or other drugs in an aquaponic system, because you would lose the most important part of the system.
Roots of plants are bathing in the water, which contains many nutrients that are available for plants. Roots work as a delicate filter, which catches only what plant needs to keep growing. Plants can grow in some of suitable substrates, or on so called rafts, which flows on the water; however they can also be bathed by dispersed water in an aeroponic system. There are many ways how to grow plants in aquaponics. More about them is written in part Systems Types. Cleaned water returns back to tanks and whole cycle begins a new.
What is the history of aquaponics?
Even though aquaponics represents big revolution in today’s agriculture and many see big future in it, it isn’t a novelty. It has rich history with natural nations. It was known by Aztecs for example. Read the history of aquaponics.
Aztec Indians in Middle America were probably the first who has used principles of combine breeding fish and growing plants. Crops were grown on artificially built islands Chinampas in lakes in Mexican valley. Farmland created this way was watered by shallow lake water, which was rich with nutrients. On these rectangle fields they were growing corn, tomatoes and beans and were fishing in canals in between them. Some of those artificial islands were preserved to nowadays and are on the list of UNESCO. In old China they have used carps and catfish to fertilize rice fields.
Present term aquaponics probably originates from the 70’s. Aquaponics as a combine system of breeding fish and growing plants was discovered by American aquaculture f armers, who were looking for solutions to lower their dependence on large amounts of fresh water for their breeding and to use the waste water for growing plants. Fish are traditionally bred in half-open offshore farms on the coasts of all seas or in freshwater ponds; however aquaponics originated from so called Recirculating Aquaculture Systems (RAS). Their advantage is that fish can be bred in larger amounts and in lower volume than in natural reservoir. Disadvantage of those intensive systems is fast accumulation of waste, which have to be released back to watercourses. Polluted water from these fish farms has to be replaced with the fresh one. This breeding consumes a lot of fresh water and releases lots of nutrients, which burdens the environment. Many kinds of filtrations and various water plants were tried for cleaning and reduction of water consumptions. Later we went to plants planted in inert substrate like for example sand or gravel. It was found that this system is also good for growing various edible plants.
The beginning of aquaponics is most often connected with work of Dr. Mark McMurtry at the North Carolina State University. In 1969 he has established the New Alchemy Institute, where he dealt with various concepts of permaculture growing. At about the same time doctor James Rakocy has created and examined an aquaponics system as his doctor’s work at the Auburn University in Alabama. After finishing his studies, he has moved to the University of the Virgin Islands in Caribbean, where he established aquaponics research program for breeding Tilapia. In 1997 James Rakocy and his colleagues invented the first big aquaponic system using the so called rafts, thus floating plates with planted vegetables in shallow tanks connected with fish tanks. Until then plants were only grown in some type of substrate, through which the water flew through.
Aquaponics in the world: Look where it works
Aquaponics is running successfully on many different places all around the world. It is developed and researched by prominent companies in the USA, England, Switzerland, Germany or northern states. Look where are aquaponics farms celebrating success.
North America and Australia
Aquaponics as a concept of alternate growing of plant and breeding fish was researched and tested in many places during the last 40 years. The first aquaponics research originated in the USA and for many years they were only experimental systems and testing of its many variations. Probably because its climatic conditions the Australia is nowadays considered a superpower with its thousands aquaponics.
Probably the biggest and most experienced company which deals in an aquaponics systems in the USA is Nelson and Pade. Till 2014 this company has built projects of total area of a few hectares. Small projects are appearing in American’s jails, to give work to inmates and also to give them new skills which they can use after returning to freedom. Many American schools and colleges have an aquaponics system nowadays as a part of agriculture research and teaching, because an aquaponics system includes problematic of many fields (engineering, agriculture, fishing, biology, chemistry, physics, construction or agribusiness).
Aquaponics got to the Europe in the last few years. Basel in Switzerland is home to company UrbanFarmers AG, which focuses on designing and realization of roof aquaponics farms in cities. They are using old ship containers, whose are rebuilt into growing systems. Berlin is home to their franchise Efficient-Farming Systems (ECF) that has opened the first bigger aquaponics farm in Germany. The farm is part of conversion of an old malt-house.
The most successful in England is GrowUp Farms Ltd., which focuses on projects in cities. Same as swiss UrbanFarmrs AG started with demonstrative ship containers that they rebuilt. GrowUp has successfully built aquaponics farm in an empty warehouse that they named „Unit 84“. The farm takes an area of 6 000 square feet in London – Beckton and produces over 20 000 kg salads and herbs and 4 000 Kg fish yearly.
Aquaponics systems are also tested within scientific grants in northern countries like Germany or Iceland. In 2013 the European Union has announced, though their scientific cooperation program with COST, memorandum about cooperation of member countries in the research of aquaponics systems as the relevant technology for sustainable production of fish and vegetables in member countries of EU.
Aquaponics projects can be found all over the world. Other countries where aquaponics is being developed are Israel, India, China and Africa.
Look at existing types of aquaponics systems
There are many kinds of aquaponics systems. They mostly differ by the arrangement of their elements, type of tanks, used technologies and size. Here you’ll find their overview.
The most common kinds of fish in aquaponics
The most bred kind of fish in aquaponics is the Nile Tilapia (Oreochromis Niloticus). The Tilapia requires warmer water, but offers good meat, endurance and fast growth. In the USA it belongs into the most favorite freshwater fish and therefore it’s breeding and selling there is relatively easy. Others, mostly in Australia bred fish are various percinae fish (breeding of Nile Tilapia is banned in Australia). Rainbow Trout (Oncorhynchus mykiss) is the other possible choice for aquaponics breeding. This kind is also perspective for Europe conditions because it is popular consuming fish there, but it requires high quality water. Another fish that can be bred in aquaponic systems is grass carp or pangasius, eventually even carp. Koi and decorative Crucians are the most common bred fish that aren’t used to consumption. They are mostly used in demonstrative systems or in decorative aquaponic ponds.
The most commonly grown plants in aquaponics
The oldest and still grown plant is Watercress, Nasturtium officinale. It is an undemanding water plan with little spicy taste, which is used in salads and is popular in France. Nowadays the most grown plants are mostly various kinds of salads and leaf vegetable, which grows very well on floating rafts. Other vegetables are tomatoes, paprika or chili peppers. Some growers are experimenting with root vegetable. Many kinds of herbs are also very favored, for example basil. From fruits, which is also very popular in aquaponics, strawberries are the most popular. These are usually grown in NFT systems or vertical towers (read below).
An aquaponics systems can be divided by their size to:
Nowadays you can buy commercially available aquaponic „mini systems“ from producers from Australia and USA. These assemblies can be an interesting addition to the kitchen, however their functionality is problematic. Small volume of water is prone to swings in a quality and these small aquaponics have to be cleaned as often as common aquariums. Plants in them will suffer from lack of some nutrients and light stress from uneven lighting.
Hobby and garden systems
These little to medium sizes of the systems are usually placed in private properties of individuals – handy man, who run aquaponics as a hobby. The most used growing substrate is gravel, ceramsite, lava gravel or eventually even floating rafts. In hobby aquaponics earthworms are often added into substrate to help with decomposing organic remains and speed up mineralization. In larger hobby system we can encounter with NFT (read below) and separation of solid waste.
Big commercial systems
Most of existing aquaponic systems designated for selling fish and vegetables belong here. Usually it consists of one or several systems in one greenhouse with growing area of tens to hundreds quarter meters. Growing plants on rafts is by far the most popular method. On the northeast of USA the type with long multilevel tanks from wood and EPDM foil by the design of Will Allen form Milwaukee is very frequent.
Big commercial systems
Into the big commercial systems comes systems with area over thousand square meters.
Another way to divide aquaponics systems is by used technology and way of breeding fish:
Growing in periodically flooded tanks filled with substrate.
It is the most common type of growing used in a small aquaponic systems. It is also called Flood & Drain. The tank is equipped with „siphon“, which after filling automatically drives water away from growing tank further into the system. This way the periodically flooded substrate (ceramsite, gravel) gives the roots of plants ideal environment rich with both nutrients and oxygen. Tanks filled with substrate are also put before growing tanks with rafts as a filter against solid particles and bio filter, where the nitrification happens.
Rafts are mostly represented by polystyrene plates, with holes for baskets or mineral wool with plant seedlings. Plans thus flow on the surface of growing tank that has shape of a shallow pool. Roots of plants then are in water column. Steady water flow or placement of air stones is required for sufficient oxygen and nutrient distribution. Advantage of this system is very easy manipulation with singular polystyrene plates, thus so with plants that are comfortably harvested.
NFT means Nutrient Film Technique. This way of growing is often used in hydroponics and it is a system of pipes with holes for individual plants. Very shallow water flows through the system. Roots of plants get nutrients from film of water and oxygen from the air.
This modified variant of NFT allows growing big amount of flowers in a small place. Water flows through the tower thanks to gravity and distributes nutrients to plants planted in special foamed matter. This kind of growing is sold as ZipGrow towers by Dr. Nate Storey at the Bright Agrotech. This method requires very good filtration of solid sludge that could clog the water distribution and even the vertical tower itself.
This method is ultimate method of hydroponic growing that can be used also in the aquaponics. Roots of plants are sprayed with drops of nutrient solution from special nozzles. This method maximizes roots oxygen supply, which thanks to that absorb nutrients better and thanks to that vegetables grow a lot faster. On the other hand it is very technically challenging and it requires very good filtration system that gets rid of the entire solid waste.
Aquariums are very aesthetic and design solutions for aquaponics in interiors. Because of size limitations they are only used in the small systems. Their advantage is the ability to watch bred fish, which are then often only decorative. Their biggest problem is ensuring good water flow, filtration of sludge and reducing algae growth so that it is always pretty to look at.
It is the most popular type of tanks used for breeding fish and growing plants. IBC are plastic containers for liquids or beverages with outer reinforcing metal cage. These containers are used for transporting various liquids and are very popular by gardeners, who are using them to collect rain water.
Their shape and capacity (1000 liters) makes them ideal for small or modular aquaponic systems and small private breeders often use them to breed fish. Another advantage is presence of the dump valve at the bottom of the tank.
Wood tanks in the multilevel system of Will Allen
This, now almost historical, probably originates from Will Allen from Milwaukee. Tanks are assembled from (larch) planks to fit area of a greenhouse and are covered from the inside with EPDM rubber. Tank for fish is in the bottom part and growing tanks are placed in several levels above them. Water is pumped to the topmost level and then it flows down through each „level“ back to the fish. Advantage of this is significant space savings and large growing area. Disadvantage of this system is mostly bad sludge management, which is filtrated only by gravel substrate. The gravel has to be „washed“ from time to time. Rectangular shape of the fish tank also limits ideal flow of water, which is worse than in a circular tank.
Circular tanks, hatcheries or pools
This is the best type of tank that is little less space saving, however it offers large volumes of water for fish breeding (thousands of liters) and very good water flowing that improves whole aquaponics cycle. Water is usually let in to the tank in one way and this creates a little whirl. This is good for healthy movement of the fish and most importantly concentrates solid part of fish waste in the center of tank. From there the sludge can be moved very fast to the setting or filtration tank. Because of that water in these systems is often very clean. Fish excrements aren’t grinded by airing and don’t set in the corners of tank, but are moved whole further into the system, where they can be processed. The volume of subtle particles, that slowly clog the system, is minimal.
Interesting way to use decorative garden ponds or tanks is linking them with hydroponic bed. However this system is only suited for hot areas, where it is able to grow under the sky for big part of a year (south of the USA, Australia). Hydroponic bed often replaces expensive filtration device. These aquaponic systems are very robust, because they are managed by the nature.