Aquaponics and Aquaculture

Aquaponics and Aquaculture are fast becoming a sustainable way of providing food security in third-world countries. While food production by means of hydroponics is reasonably easy to sustain aquaponics and aquaculture require a more advanced approach due to so much more variables involved. Growing fish in a controlled environment is very rewarding but at the same time very challenging, and costly. This page is an introduction to these concepts. Follow the links for more information and online resources.

Definitions

Hydroponics: Cultivating plants in water, often referred to as soilless gardening. This is a relatively easy way of cultivating crops in water.

Aquaculture: Raising aquatic animals such as snails, fish, crayfish or prawns in fish ponds, tanks or dams for private or commercial use.

Aquaponics: Combines aquaculture with hydroponics in a symbiotic environment. In aquaculture, effluents accumulate in the water, increasing toxicity for the fish. This water is led to a hydroponic system where the by-products from the aquaculture are broken down by nitrogen-fixing bacteria, then filtered out by the plants as vital nutrients, after which the cleansed water is recirculated back to the fish. This is a more complicated system.

More About Aquaponics

Aquaponics produces both protein (fish) and vegetables in the same system. Aquaponics combines both systems and in doing so cancels out the negative aspects of each. Instead of adding toxic chemical solutions to grow plants, aquaponics uses highly nutritious fish effluent that contains almost all the required nutrients for optimum growth. Instead of discharging water, aquaponics uses the plants and the media in which they grow to clean and purify the water, after which it is returned to the fish tank. This water can be reused indefinitely and will only need to be replaced when it is lost through transpiration and evaporation. For someone to be able to be successful at aquaponics farming one needs to have a basic knowledge of both these systems. The more difficult one is aquaculture, growing, and breeding fish.

Documents Relevant to Aquaculture in South Africa

Guidelines for freshwater aquaculture and inland fisheries in South Africa
To provide guidance on the processes, steps, and procedures to follow for the authorization of an aquaculture activity and inland fisheries b) To ensure sustainable use of aquatic resources and c) To provide guidance on the process in terms of other legislation(s) required or to be considered when an aquaculture activity is considered.

Introduction to Aquaculture in the Eastern Cape (South Africa)
The Department of Economic Development and Environmental Affairs (DEDEA) has compiled this Introduction to Aquaculture in the Eastern Cape to
assist stakeholders with finding basic information pertaining to this sector in the province.

When considering Aquaculture as an income-generating community project AquacultureInnovations strongly recommends the following:
· A Commercial Mandate

· A Strong Commercial Partner

· Discipline
· Extensive Training
· Shareholding
· Employment

Fish Species Suited for Aquaculture in South- and Southern Africa

Oreochromis niloticus Linnaeus (Nile Tilapia)

Habitat: Nile tilapia is a tropical species that prefer to live in shallow water. The lower and upper lethal temperatures for Nile tilapia are 11-12 °C and 42 °C, respectively, while the preferred temperature ranges from 31 to 36 °C. It is an omnivorous grazer that feeds on phytoplankton, periphyton, aquatic plants, small invertebrates, benthic fauna, detritus, and bacterial films associated with detritus. Nile tilapia can filter feed by entrapping suspended particles, including phytoplankton and bacteria, on mucous in the buccal cavity, although its main source of nutrition is obtained by surface grazing on periphyton mats. Sexual maturity in ponds is reached at an age of 5-6 months. (This species is not allowed in South Africa)

Links
Food and Agriculture Organization of the United Nations

Oreochromis mossambicus (Mozambique Tilapia)

Habitat: Freshwater and brackishwater inhabitants. Lives in warm, weedy pools of sluggish streams, canals, and ponds. Is mainly diurnal. Occurs at temperatures ranging from 8º to 42º C. The female usually incubates the spawn; the male should be removed as soon after spawning as possible. May form schools. Omnivorous feeds on almost anything from algae to insects but also crustaceans, and fishes. Can be reared under hypersaline conditions. Spawn all year round when kept in warm water (above 20º C). Grows up to 36cm.

Links

Food and Agriculture Organization of the United Nations

Clarias gariepinus (Catfish)

Habitat: Freshwater, widely tolerant of extreme environmental conditions. The presence of an accessory breathing organ enables this species to breathe air when very active or under very dry conditions. Bottom feeder which occasionally feeds at the surface. Omnivorous, a general scavenger. Feeds on insects, crabs, plankton, snails, and fish but also takes young birds, rotting flesh, plants, and fruits. Grows up to 150 cm. (Indigenous to South- and Southern Africa)

Links

"Artificial Reproduction and Pond Rearing of the African Catfish Clarias Gariepinus in Sub-Saharan Africa" - A Handbook Food and Agriculture Organization of the United Nations

Other Aquatic Species Suited for Aquaculture

Cherax tenuimanus (Marron)

The marron, Cherax tenuimanus , is a freshwater crayfish species native to the southwestern region of Western Australia. The optimum growth rates for marron are achieved between 170C and 250C. Growth will decline and eventually cease when temperatures hit below 12.50C. Mortalities will start to occur when temperatures reach 300C. Marron has been grown successfully commercially. They have many economic attributes that make them suitable species for aquaculture. Some of these include their large size, good feed conversion efficiency, and their direct life cycle. Marron farms are also relatively inexpensive to construct compared to other forms of farming with some people utilizing existing farm dams to produce marron.

Links

• Biodiversity Risk and Benefit Assessment for Smooth Marron (Cherax cainii) and Hairy Marron (Cherax tenuimanus) in South Africa

• Fisheries Fact Sheet - Marron (Government of Western Australia Department of Fisheries)

• The Marron Fishery - (Government of Western Australia Department of Fisheries)

• Marron: Taxonomy, Biology and Production (Department of Agriculture, Forestry and Fisheries South Africa)

Aquaculture Research Links

If you are interested in and familiar with research jargon then these websites are a great source of information. Some of these articles are open access, meaning one has free access to view and download the articles.
• Journal of Aquaculture Research & Development - Open access.
• North American Journal of Aquaculture - Open and paid access.

• Directory of Open Access Journals This is a database of open-access research journals related to the field of Aquaculture and Fisheries. It is a great resource.

Aquaculture Solutions
Indonesia
"eFishery aims to provide fisheries products as the main source of animal protein that is not only rich in nutrients but also accessible to everyone. That being said, we are here to take part in the Aquaculture revolution."

South Africa

Aquaculture Innovations is a service provider to the Aquaculture industry. They assist existing aquaculturists as well as new entrants into the industry.

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