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 10,000kg/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.
{{procontable | pro=
- Fish may pose a health risk if improperly prepared or cooked. <br> - Requires abundance of fresh water. <br> - Requires large land (pond) area. <br> - May require expert design and installation.
}}
==Adequacy==
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.
==Acknowledgements==
{{:Acknowledgements Sanitation}}
==Referencesand external links== * Elizabeth Tilley et.al (2008). [http://www.eawag.ch/organisation/abteilungen/sandec/publikationen/publications_sesp/downloads_sesp/compendium_high.pdf Compendium of Sanitation Systems and Technologies] ([http://www.eawag.ch/organisation/abteilungen/sandec/publikationen/publications_sesp/downloads_sesp/compendium_low.pdf low res version]). Department of Water and Sanitation in Development Countries ([http://www.sandec.ch/ Sandec]) at the Swiss Federal Institute of Aquatic Science and Technology (Eawag). (Provides a full overview of sanitation systems.)
* Cointreau, S., et al. (1987). Aquaculture with treated wastewater: a status report on studies conducted in Lima, Perú. Technical Note 3. UNDP/World Bank, Washington D.C. USA. 1987.