Editing Ammonia (section)

=== Aquaculture ===
Ammonia toxicity is believed to be a cause of otherwise unexplained losses in [[fish hatcheries]]. Excess ammonia may accumulate and cause alteration of metabolism or increases in the body pH of the exposed organism. Tolerance varies among fish species.<ref name="Oram">{{Cite web|url = http://www.water-research.net/index.php/ammonia-in-groundwater-runoff-and-streams|title = Ammonia in Groundwater, Runoff, and Streams|access-date = 3 December 2014|website = The Water Centre|last = Oram|first = Brian}}</ref> At lower concentrations, around 0.05&nbsp;mg/L, un-ionised ammonia is harmful to fish species and can result in poor growth and feed conversion rates, reduced fecundity and fertility and increase stress and susceptibility to bacterial infections and diseases.<ref>{{Cite book|title = Managing ammonia in fish ponds|last1 = Hargreaves|first1 = J.A.|publisher = Southern Regional Aquaculture Center|year = 2004|last2 = Tucker|first2 = C.S.}}</ref> Exposed to excess ammonia, fish may suffer loss of equilibrium, hyper-excitability, increased respiratory activity and oxygen uptake and increased heart rate.<ref name="Oram" /> At concentrations exceeding 2.0&nbsp;mg/L, ammonia causes gill and tissue damage, extreme lethargy, convulsions, coma, and death.<ref name="Oram" /><ref name="Sergeant-2014">{{Cite journal|url = http://www.pollutionsolutions-online.com/articles/water-wastewater/17/chris_sergeant/the_management_of_ammonia_levels_in_an_aquaculture_environment/1557/|title = The Management of Ammonia Levels in an Aquaculture Environment|last = Sergeant|first = Chris|date = 5 February 2014|journal = Water/Wastewater|access-date = 3 December 2014}}</ref> Experiments have shown that the lethal concentration for a variety of fish species ranges from 0.2 to 2.0&nbsp;mg/L.<ref name="Sergeant-2014" />

During winter, when reduced feeds are administered to aquaculture stock, ammonia levels can be higher. Lower ambient temperatures reduce the rate of algal photosynthesis so less ammonia is removed by any algae present. Within an aquaculture environment, especially at large scale, there is no fast-acting remedy to elevated ammonia levels. Prevention rather than correction is recommended to reduce harm to farmed fish<ref name="Sergeant-2014" /> and in open water systems, the surrounding environment.