Fish Pond (Aquaculture)

Fish can be grown in ponds that receive effluent or sludge where they can feed on algae and other organisms that grow in the nutrient-rich water. The fish, thereby, remove the nutrients from the wastewater and are eventually harvested for consumption.

Three kinds of aquaculture designs for raising fish exist:

1) fertilization of fish ponds with effluent;

2) fertilization of fish ponds with excreta/sludge; and

3) fish grown directly in aerobic ponds

Fish introduced into aerobic ponds can effectively reduce algae and help control the mosquito population. It is also possible to combine fish and floating plants in one single pond.

The fish themselves do not dramatically improve the water quality, but because of their economic value they can offset the costs of operating a treatment facility. Under ideal operating conditions, up to 10,000 kg/ha of fish can be harvested. If the fish are not acceptable for human consumption, they can be a valuable source of protein for other high-value carnivores (like shrimp) or converted into fishmeal for pigs and chickens.

Design Considerations

The design should be based on the quantity of nutrients to be removed, the nutrients required by the fish and the water requirements needed to ensure healthy living conditions (e.g., low ammonium levels, required water temperature, etc.). When introducing nutrients in the form of effluent or sludge, it is important to limit the additions so that aerobic conditions are maintained. BOD should not exceed 1 g/m2/d and oxygen should be at least 4 mg/L. Only fish tolerant of low dissolved oxygen levels should be chosen. They should not be carnivores and they should be tolerant to diseases and adverse environmental conditions. Different varieties of carp, milkfish and tilapia have been successfully used, but the specific choice will depend on local preference and suitability.

Appropriateness

A fish pond is only appropriate where there is a sufficient amount of land (or pre-existing pond), a source of fresh water and a suitable climate. The water used to dilute the waste should not be too warm, and the ammonium levels should be kept low or negligible because of its toxicity to fish.

This technology is appropriate for warm or tropical climates with no freezing temperatures, and preferably with high rainfall and minimal evaporation.

Health Aspects/Acceptance

Where there is no other source of readily available protein, this technology may be embraced. The quality and condition of the fish will also influence local acceptance. There may be concern about contamination of the fish, especially when they are harvested, cleaned and prepared. If they are cooked well, they should be safe, but it is advisable to move the fish to a clear-water pond for several weeks before they are harvested for consumption. WHO guidelines on wastewater and excreta use in aquaculture should be consulted for detailed information and specific guidance.

Operation & Maintenance

The fish need to be harvested when they reach an appropriate age/size. Sometimes after harvesting, the pond should be drained so that (a) it can be desludged and (b) it can be left to dry in the sun for 1 to 2 weeks to destroy any pathogens living on the bottom or sides of the pond. Workers should wear appropriate protective clothing.

References

Further Readings

  • Cover image of a reference book or miscellany.

    TILLEY, E.; ULRICH, L.; LUETHI, C.; REYMOND, P.; SCHERTENLEIB, R.; ZURBRUEGG, C. (2014): Compendium of Sanitation Systems and Technologies (Arabic). 2nd Revised Edition. Duebendorf, Switzerland: Swiss Federal Institute of Aquatic Science and Technology (Eawag). PDF

    This is the Arabic version of the Compendium of Sanitation Systems and Technologies. The Compendium gives a systematic overview on different sanitation systems and technologies and describes a wide range of available low-cost sanitation technologies.

  • Cover image of a reference book or miscellany.

    EDWARDS, P. ; Asian Institute of Technology (Editor) (2008): Key Issues in the Safe Use of Wastewater and Excreta in Aquaculture. (pdf presentation). Bangkok, Thailand: World Toilet Organisation. URL [Accessed: 19.02.2010]. PDF

    This document is a guidance note for program managers and engineers that summarises the key issues of the 3. Volume of the WHO Guidelines that focuses on the safe use of wastewater and excreta in aquaculture.

  • Cover image of a reference book or miscellany.

    EWARDS, P. (Editor); PULLIN, R. (Editor) (1990): Wastewater-fed aquaculture. . Calcutta, India: International seminar on wastewater reclamation and reuse for aquaculture. URL [Accessed: 18.01.2011]. PDF

  • Cover image of a reference book or miscellany.

    IQBAL, S.; EAWAG (Editor) (1999): Duckweed Aquaculture. Potentials, Possibilities and Limitations for Combined Wastewater Treatment and Animal Feed Production in Developing Countries. Duebendorf: Swiss Federal Institute of Aquatic Science and Technology (Eawag). URL [Accessed: 15.04.2014]. PDF

    This literature review provides a first overview of the possibilities, potentials and limits of duckweed aquaculture and its combined use in wastewater treatment and animal feed production in low and middle-income countries. It is somewhat limited as critical literature on duckweed field use is scarce and difficult to obtain (e.g. unpublished internal documents).

  • Cover image of a reference book or miscellany.

    JOHNSON COINTREAU, S. (Editor) (1987): Aquaculture with Treated Wastewater. A Status Report on Studies Conducted in Lima, Peru. Washington: The World Bank. URL [Accessed: 15.04.2014]. PDF

    This study has shown that significant quantities of protein for either human consumption or livestock feed could be produced from wastewater—based aquaculture, which could be integrated with sewage stabilization lagoon systems. Reuse of treated sewage to fertilize the microbial food chain for aquaculture presents one of the most economic resource recovery options for cities in developing countries.

  • Cover image of a reference book or miscellany.

    FAO (Editor); NACA (Editor); WHO (Editor) (1999): Food Safety Issues Associated with Products from Aquaculture. Washington: World Health Organization (WHO). URL [Accessed: 15.04.2014]. PDF

    This is the report of a Study Group that considered food safety issues associated with farmed finfish and crustaceans. The principal conclusion was that an integrated approach — involving close collaboration between the aquaculture, agriculture, food safety, health and education sectors — is needed to identify and control hazards associated with products from aquaculture.

  • Cover image of a reference book or miscellany.

    JUNGE-BERBEROVIC, R.; University of Applied Sciences Waedenswil. (Editor) (2001): Possibilities and Limits of Wastewater-fed Aquaculture. Waedenswil: University of Applied Sciences Waedenswil. URL [Accessed: 19.02.2010]. PDF

    At the University of Applied Sciences Waedenswil, Switzerland, wastewater-fed aquaculture is a research focus since 1993. This paper summarises some of the results and insights gained since then.

  • Cover image of a reference book or miscellany.

    MARA, D. (2003): Domestic Wastewater Treatment in Developing Countries. London: Earthscan. URL [Accessed: 15.04.2014]. PDF

    The primary emphasis of the book is on low-cost, high-performance, sustainable domestic wastewater treatment systems. Most of the systems described are ‘natural’ systems – so called because they do not require any electromechanical power input. The secondary emphasis is on wastewater re-use in agriculture and aquaculture.

  • Cover image of a reference journal article.

    MARA, D.D. (2004): Wastewater Re-use in Aquaculture. In: Domestic Wastewater Treatment in Developing Countries, 252.URL [Accessed: 17.02.2011].

    This chapter gives a comprehensive overview on what is aquaculture, including some examples and elements useful for dimensioning.

  • Cover image of a reference book or miscellany.

    PESCOD, M.B. (1992): Wastewater Treatment and Use in Agriculture. Rome: Food and Agriculture Organisation of the United Nations (FAO). URL [Accessed: 25.10.2011].

    This Irrigation and Drainage Paper is intended to provide guidance to national planners and decision-makers, agricultural and municipal managers, field engineers and scientists, health and agricultural field workers, wastewater treatment plant operators and farmers. Consequently, it covers a broad range of relevant material, some in considerable depth but some more superficially. It is meant to encourage the collection, treatment and use of wastewater in agriculture in a safe manner, with maximum advantage taken of this resource. Informal, unplanned and unorganized wastewater use is not recommended, nor is it considered adviseable from the health or agricultural points of view.

  • Cover image of a reference book or miscellany.

    ROSE, D.G. (1999): Community-Based Technologies for Domestic Wastewater Treatment and Reuse- options for urban agriculture. Ottawa: International Development Research Center Canada (IDRC). PDF

    The report suggests that emerging trends in low-cost, decentralised naturally-based infrastructure and urban wastewater management which promote the recovery and reuse of wastewater resources are increasingly relevant. Technologies for these sanitation options are presented. The concept of managing urban wastewater flows at a decentralised or "intermediate" level, based on micro watersheds, is explored. Effluent treatment standards that are currently accepted in order to protect public health and safety are reviewed.

  • Cover image of a reference book or miscellany.

    VARON, M. P.; MARA, D. D. (2004): Waste Stabilisation Ponds. (pdf presentation). Delft: International Water and Sanitation Centre . URL [Accessed: 17.05.2012]. PDF

    This document provides information and instructions on waste stabilisation ponds. Various case studies are mentioned, e.g. the wastewater-fed fishponds in Calcutta in India.

Case Studies

Training Material

  • Cover image of a reference book or miscellany.

    EDWARDS, P. (2008): Volume III: Wastewater and excreta use in aquaculture.. (pdf presentation). Bangkok, Thailand: Asian Institute of Technology. PDF

    This presentation gives a detailed overview on the 3. volume of the WHO guidelines on the safe use of wastewater and excreta in aquaculture including many pictures of existing wastewater-fed aquaculture and fish pond technologies all over the world. Apart from the health risk and appropriate health protection measures, a lot of information on socio-cultural, environmental and economic aspects is given as well as supporting information on planning and implementation of sewage-fed fish ponds.

Important Weblinks

  • http://www.enaca.org/ [Accessed: 09.02.2010]

    The official homepage of Network of Aquaculture Centres in Asia-Pacific provides up to date information on ecological, economic and technological aspects of aquaculture. Many open source documents (manuals, reports, case studies etc.) are available here.

  • http://www.unep.or.jp/ [Accessed: 09.02.2010]

    The UNEP homepage provides an international source book on environmentally sound technologies for wastewater and storm water management including a chapter on aquaculture.

  • http://www.fao.org/docrep/t0551e/t0551e09.htm [Accessed: 09.02.2010]

    The FAO homepage provides an online document on wastewater treatment and use in agriculture with an extra chapter on wastewater use in aquaculture. Various economical, ecological, technical and biological aspects are explained.