Aquaponics is the ideal answer to a fish farmers problem of disposing of nutrient rich water and a hydroponic growers need for nutrient rich water. Hydroponics is growing plants in a solution of water and nutrients, without soil. The solution is created by adding the elements a plants needs to water, which is fed directly to the plant’s roots. In some hydroponic systems the roots are in a growing medium which keeps them moist, aerated and helps to support the plant. Hydroponics provides the plant with the ideal water and nutrient ratios and optimum conditions for growth.In aquaculture, the water quickly becomes nutrient rich due to the fish digesting their food and excreting waste. The waste water is usually filtered and/or disposed of to keep the tank water free of toxic buildups.In aquaponics, the fish waste provides a food source for the growing plants and the plants provide a natural filter for the fish. This creates a mini ecosystem where both plants and fish can thrive. Aquaponics is the ideal answer to a fish farmers problem of disposing of nutrient rich water and a hydroponic growers need for nutrient rich water.Commercially, aquaponics is in its infancy but, as the technology develops and is refined, it has the potential to be a more efficient and space saving method of growing fish, vegetables and herbs. By incorporating aquaponics, hydroponic growers can eliminate the cost and labor involved in mixing a fertilizer solution and commercial aquaculturists may be able to drastically reduce the amount of filtration needed in recirculating fish culture. Although there is currently a limited number of commercial aquaponic operations, many people are expressing a strong interest in this intensive method of food production.Although the practices of fish farming and soil less plant culture have been traced to ancient times, the combination of the two is quite new. Research in aquaponics began in the 1970’s and continues today. Several Universities worldwide are dedicating resources to further the technology. At the University of the Virgin Islands, Dr. James Rakocy and his associates have developed a commercially viable aquaponics system designed for use in the tropics where natural fish populations have been depleted and most agricultural products must be imported.On a hobby scale, aquaponics has the potential to catch on quickly. A home aquarium, with ornamental or food fish, can be combined with a mini garden, growing herbs, vegetables or flowers. A hobby system can serve as a beautiful show piece or a food production system, depending on the size. Many backyard gardeners are setting up systems to grow hundreds of pounds of fish and all the fresh vegetables a family needs. 

What is aquaponics?

Aquaponics is the combination of recirculation aquaculture and hydroponics.  In aquaponics, you grow plants and fish together in one integrated system.  The fish waste provides a food source for the growing plants and the plants provide a natural filter for the water the fish live in.  This creates a sustainable ecosystem where both plants and fish can thrive. Aquaponics is the ideal answer to a fish farmers problem of disposing of nutrient rich water and a hydroponic growers need for nutrient rich water

Is aquaponics organic?

Aquaponics is a completely natural process which mimics all lakes, ponds, rivers and waterways on earth.  The only input to an aquaponic system is fish food.  The fish eat the food and excrete waste, which is converted (by beneficial bacteria) to a form that that plants can use.  In consuming these nutrients, the plants help to purify the water.  You can not use herbicides, pesticides or other harsh chemicals in an aquaponic system, making the fish and plants healthful and safe to eat.This process could not be more organic but getting a USDA organic certification for a culture system that does not use soil is tricky.  A couple of commercial growers in the US have had their plants certified as organic.  The USDA has not finalized organic certification standards for fish yet.

What are the benefits of growing Aquaponically?

The combination of aquaculture and hydroponics is quite new and the potential for using aquaponics to grow high quality food around the world is tremendous.  Here are some of the many advantages of aquaponic food production: Aquaponics utilizes the nutrient rich water from aquaculture that otherwise would have been a waste product or would need to be filtered in a costly manner.Aquaponics eliminates the cost and time involved with mixing traditional hydroponic nutrients.Aquaponics provides a truly organic, natural form of nutrients for the plants.By eliminating the soil in vegetable production, you eliminate all soil borne disease.Aquaponics uses a fraction of the water that traditional field production does because no water is wasted or consumed by weeds.In aquaponics, plant spacing can be very intensive, allowing you to grow more plants in a given space.With high stocking densities in the fish tank, plants will quickly grow and develop in an aquaponic system.In aquaponics there cannot be any pesticides or herbicides used, making the end product healthier and safer.If your climate permits or if you are growing in a greenhouse, you can grow crops in an aquaponic system year-round.  

Methods of Aquaponics

There are many different configurations of aquaponic systems.  The components common to every aquaponic system are the fish tank and a plant bed. The variables include filtration components, plumbing components, the type of plant bed and the amount and frequency of water circulation and aeration. Generally speaking, systems that utilize some filtration to remove the solid fish waste will have higher production of fish and plants than those that don't use filtration.There are three primary aquaponic methods emerging in the industry.  Each if these methods is based on a hydroponic system design, with accommodations for fish and filtration.  

Raft

In a raft system (also known as float, deep channel and deep flow) the plants are grown on Styrofoam boards (rafts) that float on top of water. Most often, this is in a tank separate from the fish tank.  Water flows continuously from the fish tank, through filtration components, through the raft tank where the plants are grown and then back to the fish tank.  The beneficial bacteria live in the raft tank and throughout the system.  The extra volume of water in the raft tank provides a buffer for the fish, reducing stress and potential water quality problems.  This is one of the greatest benefits of the raft system.  In addition, the University of the Virgin Islands and other research programs have worked to develop and refine this method for over 25 years.  The raft system is a well developed method with very high production per square foot.  In a commercial system, the raft tanks can cover large areas, best utilizing the floor space in a greenhouse.  Plant seedlings are transplanted on one end of the raft tank.  The rafts are pushed forward on the surface of the water over time and then the mature plants are harvested at the other end of the raft.  Once a raft is harvested, it can be replanted with seedlings and set into place on the opposite end.  The optimizes floor space, which is especially important in a commercial greenhouse setting.

NFT

NFT (Nutrient Film Technique) is a method in which the plants are grown in long narrow channels.  A thin film of water continuously flows down each channel, providing the plant roots with water, nutrients and oxygen.  As with the raft system, water flows continuously from the fish tank, through filtration components, through the NFT channels where the plants are grown and then back to the fish tank.  In NFT, a separate bio filter is required, however, because there is not a large amount of water or surface for the beneficial bacteria to live.  In addition, the plumbing used in a hydroponic NFT system is usually not large enough to be used in aquaponcis because the organic nature of the system and "living" water will cause clogging of small pipes and tubes.  NFT aquaponics shows potential but, at this time, it is used less than the other two methods discussed here.

Media-filled Bed

A media-filled bed system uses a tank or container that is filled with gravel, perlite or another media for the plant bed.  This bed is periodically flooded with water from the fish tank.  The water then drains back to the fish tank.  All waste, including the solids, is broken down within the plant bed.  Sometimes worms are added to the gravel-filled plant bed to enhance the break-down of the waste.  This  method uses the fewest components and no additional filtration, making it simple to operate.  The production is, however, much lower than the two methods described above.  The media-filled bed is often used for hobby applications where maximizing production is not a goal. 

Commercial Aquaponics

Aquaponics is the combination of recirculation aquaculture and hydroponics. . Commercial Aquaponics is a young sector of agriculture but one with great potential.  There are commercial aquaponic farms in the US, Canada, Mexico, Australia and a few other countries but, as of now, the total number of commercial enterprises is quite small.  This is due to the fact that combining aquaculture and hydroponics is fairly new technology.Yes, aquaponics is quite new but it is not unproven.  Research scientists at the University of the Virgin Islands have been developing commercially-viable aquaponic systems for nearly 25 years and commercial growers and many other Universities have contributed to the research and development of aquaponics technology.  Aquaponics can fill a niche market for premium quality crops or it can provide staples for a village in a developing country.  (See Village Aquaponics article)  Most commercial growers use a greenhouse to protect the plants and fish from harsh environmental conditions and pest insects.  In a greenhouse, floor space must be maximized to reduce costs and increase production. The production can be very high in a commercial aquaponic system when plant spacing is maximized and the fish are fed a proper and balanced diet.  The daily work involved in a commercial aquaponic venture includes feeding the fish and cleaning the filters, seeding, transplanting and harvesting the plants and packaging the produce for sale.  The fish are harvested periodically, with the frequency dependant on the size of the system, the number of fish tanks and the market demand.There is a growing need for aquaponics and controlled environment agriculture.  The past several years of the fresh food industry have been marred by continued incidence of food contamination and consumer illness.  Causes range from impure water to unsanitary conditions in fields and packing facilities, to imports that are not inspected.  Nearly 99 % of the fresh food imported into the US is not inspected.  Much of this food, including what is labeled as organic, is coming from countries without strict safety, nutritional or environmental regulations.   Food grown in the US that is processed in massive processing and packaging facilities has proven to be susceptible to contamination as well.In a controlled environment greenhouse, a grower has the ability to enforce a bio-security program that will keep the food free of contamination.  In addition, the ability to be close to the marketplace eliminates the long-distance travel (on average over 2000 miles) that most fresh food travels in the US.  An aquaponic farm can be a rewarding and profitable business for a family or individual.  It can also tap into the "agri-tourism" craze and earn extra income from it.

Greenhouses and Controlled Environment Agriculture

Your hydroponic or aquaponic growing system allows you to grow premium crops in an environmentally friendly way.  Controlling the environment allows you to provide the exact conditions your crops need to thrive.  Hydroponics and/or aquaponics go hand-in-hand with a controlled environment greenhouse.  Separately, they are tools to grow crops.  Together, they create the ultimate method of food production.

Greenhouse, hothouse, glasshouse...these are all terms used to describe plastic or glass covering over a crop.  Controlled environment agriculture takes the benefits a crop cover provides and enhances them with precise environmental control which provides exactly the environmental conditions your crop needs. 

We have experience with single bay Quonset-style greenhouses, multi bay greenhouses, naturally-ventilated and retractable roof style greenhouse.  We assist our clients in choosing the right greenhouse for their locations, climate, crop and budget!

Educational Applications

Aquaponics and hydroponics are both excellent means of demonstrating many principles of science, agriculture, math and business in all grade levels and for home schooling.  Applications of these technologies are only limited by ones imagination.  A unit in hydroponics or aquaponics enforces practical uses of chemistry, mathematics, physics, economics and engineering. The monitoring and care of a hydroponic or aquaponic system by students helps instill a sense of responsibility, inspires creativity and creates excitement in the learning environment.

A small hydroponic garden can sit on a counter top and be used to demonstrate botany, horticulture, hydroponics (soil less plant culture), plant science, nutrition, physiology and care, nutrient and pH testing, pH relationships, plant usage of nutrients, seed germination, photosynthesis and light and plant development.

An aquaponic system combines hydroponics with aquaculture in a recirculating system.  In addition to the plant sciences, aquaponics incorporates and demonstrates many of natures natural cycles, nitrification, biology, fish anatomy and nutrition and high-tech agriculture.

A unit in hydroponics or aquaponics can be started at the beginning of a semester and run through the entire semester, allowing the educator to present the individual concepts and lessons as the plants and fish develop and grow.  A small hydroponic or aquaponic system can sit on a spare counter top.  Larger systems can be placed on the floor of a classroom, in a windowsill or a greenhouse.

Recommended Plants and Fish in Aquaponics 

The fish and plants you select for your aquaponic system should have similar needs as far as temperature and pH.  There will always be some compromise to the needs of the fish and plants but, the closer they match, the more success you will have.  As a general rule, warm, fresh water, fish and leafy crops such as lettuce and herbs will do the best.  In a system heavily stocked with fish, you may have luck with fruiting plants such as tomatoes and peppers.

Fish that have been raised in aquaponics with good results:

• tilapia

• large mouth bass

• sunfish

• crappie

•  koi

• fancy goldfish

• pacu

• various ornamental fish such as angelfish, guppies, tetras, swordfish, mollies

• blue gill/breem

• carp

• barramundi

• silver perch, golden perch, yellow perch
  

Plants that will do well in any aquaponic system:

• any leafy lettuce

• pak choi

• spinach

• arugula

• basil

• mint

• watercress

• chives

• most common house plants

Plants that have higher nutritional demands and will only do well in a heavily stocked, well established aquaponic system:

• tomatoes

• peppers

• cucumbers

• beans

• peas

• squash