Aquaponics - Definition

Aquaponics is a system of food production that merges the conventional aquaculture (which is the raising of aquatic animals like snails, fish, crabs or shrimp in ponds), with the hydroponics (the culture of plants in soil less conditions) in a symbiotic environment.

In traditional aquaculture, aquatic effluents from the aquatic animals accumulate in the water, raising the toxicity for the aquatic organisms. This effluent rich water is redirected to the hydroponic system, where the toxic components generated in aquaculture are transformed by nitrification bacteria, and then filtrated by the plants as nutrients. After this, the purified water is recirculated again to the animals.

Components

Aquaponics consists of two main components, the aquaculture section to raise aquatic animals, and the hydroponic section to grow plants.

Aquatic effluents, resulting from uneaten food or raising animals like fish, accumulate in the water because of the closed recirculating nature of most of the aquaculture systems. This effluent-rich water becomes toxic for aquatic animals in high concentrations, but these effluents contain essential nutrients for the normal grow of plants.

Even as the aquaponics system is mainly build with this two components, usually it is grouped in different subsystems responsible for the removal of solid waste, for adding bases to neutralize acids, or to maintain water oxygen levels. Most common components include:

• Rearing tank: the tanks for raising and feeding the fish.
• Settling basin: a unit for catching uneaten food and detached bio films, and for settling out fine particulates.
• Bio filter: a place where the nitrification bacteria can grow and convert ammonia into nitrates, which are usable by the plants.
• Hydroponics subsystem: the portion of the system where plants are grown by absorbing excess nutrients from the water.
• Sump: the lowest point in the system where the water flows to and from which it is pumped back to the rearing tanks.

Depending at the cost and complexity level of the aquaponics system, the hydroponics system, the settling basin and the bio filter can be merged into one single unit or subsystem, which makes the water flow directly from the aquaculture to the hydroponic section directly.

Aquaponics - History

The principles of aquaponics have been used from a long time ago, but there is much discussion about when does this technique started.

The Aztecs build agricultural islands know as chinampas, and for many people those are the first form of aquaponics in history. These islands were created in lagoons and normally were fixed to the bottom of the water body, but in some occasions were left to drift freely.

The plants growing on this islands were fed with the nutrients available in the lagoon, and were an important component of the Aztec nutrition.

At the south part of China and Thailand the rice farmers grew rice in flooded fields mixing the rice and fish. This is another of the early aquaponics systems. This type of system extended to many regions of Asia, and were used to supplement the meals of farming villages.

In recent times, the development of aquaponics as it is being used in present times, is mostly because of the works of the New Alchemy Institute, and the work of Dr. Mark McMurtry et al. at the South Caroline University.

Dr. James Rakocy and his colleagues at the Virgin Islands University began in 1997 the development of deep water beds for hydroponics using an aquaponics commercial development.

At the island of Barbados there was an initiative to create acuaponic systems in houses, as a way to reduce the dependency of imported food at the island.

But one of the channels that have contributed the most to divulge the aquaponic system, and to be able to exchange opinions and experiences is the internet. Many user groups are active around the world, and many communities are working in which you can get a lot of information about aquaponics.

Aquaponics - The beginning

From sometime ago, I have been interested in aquaponics, and to develop a system that allows my family to get healthy fresh food to eat at home.

After a long time undecided about it, I think it is time to get my hands dirty and start working on it. Most of the information on aquaponics is not readily available on Spanish, and even less is available in Costa Rica, so I decided to document the work I do on the project, as well as the research and tests I will do on this site. I will be posting the information in both Spanish and English.

I hope that as time goes on, the information I gather here will be useful to other people that are also interested in developing a food production system that can generate great benefits for everybody.

Regards,

Marco