aubergines. However, several nontraditional hydroponic crops have
also been grown using this system
including radishes, beets, papaya
and even bananas. The system can
therefore be adjusted for the production of regionally preferred food
crops. For certain crops additional
fertilization of certain nutrients
might be needed to reach the production potential of the crop but
even without it, nutritious food can
be produced. Tilapia is still the most
popular fish species to use since
they grow quickly and are relatively
easy to raise but catfish, carp and
even shrimp have been used depending on the type of system and
climatic conditions. Care should be
taken however to have a biofilter
placed within the system which can
break down the ammonium to nitrates, which is the preferred nitrogen source of most plants.
to areas where water might be limited. Since water is re-circulated
continuously, the amount of water
used to produce the crops is as
much as 10 times less than the
amount of water used for producing crops in the soil. The better the
quality of water being used the
longer water can be re-cycled and
the higher the water-use efficiency
of the system. The ideal will be to
link the system to a rainwater collection unit that can top-up the
water levels with pure water when
needed. It is therefore definitely an
environmentally friendly method of
food production that does not put
further strain on our ever decreasing natural resources.
One of the most important advantages of these systems is that
they are ideally suited for areas not
traditionally linked to agriculture.
This includes areas where the soil is
degraded or where land is not
available for food production such
as in urban and peri-urban areas.
With the high rate of urbanization
in many developing countries it
becomes even more essential to
increase the availability of fresh
food in these highly populated areas. The system is also ideally suited
Food insecurity is often caused not
by the lack of production of food
but by disruptions in the supply
chains. Long supply chains also can
lead to a decrease in the nutritional
quality of food. For future food security it is essential to develop
methods to increase food production on a regional basis, therefore
increasing the availability of fresh
food and providing people with the
capacity to take responsibility for
their own family or community’s
food production. There is a huge
potential for aquaponics in ensuring food security in developing
countries based on the relative simplicity of the system - once set-up
and in production - and the limited
The tilapia linked to the vertical
growing system for this restaurant.
A variety of crops grown in
a aquaponics system where
floating beds are used.
need for outside inputs, if managed
properly. Especially in areas where
people rely on staple crops such as
wheat and maize, the nutrient rich
vegetables that can be produced in
such a system combined with the
protein from the fish can be vital in
enabling food security. However,
the system does need a constant
supply of electricity for all the
pumps to keep working and also
some level of technical training and
support seems to be essential for
the successful operation of these
systems.
Although this system is ideal to assist in making nutritious food available to a household or community
in a subsistence farming set-up, the
volume of food that can potentially
be generated in a single aquaponic
unit also make it an ideal small
business venture, building the economic stability of individuals and
communities. In this case it will be
essential to support these entrepreneurs so that the maximum yields
can be obtained from their systems
while minimizing risks posed by
possible pest and disease problems. Additionally where these systems have been installed at schools,
they have proved a valuable tool in
educating children the basic concepts relating to sustainable farming and the value of and efficient
use of natural resources.
Lettuce growing in a vertical growing system in an aquaculture system that was built for a restaurant.