Biological and Chemical Denitrification Systems in Aquaculture – A Review

In recent decades, aquaculture has intensified due to its capacity for efficient food production in controlled/semi-controlled systems that are not dependent on seasonal variations, which has not only contributed to sustainability and food security but has also been associated with potential environmental problems.Among these issues, the production of nitrogen compounds from aquaculture systems stands out, particularly nitrates and nitrites, which, under improper management conditions, can harm farmed species and lead to eutrophication when discharged into the environment, with harmful consequences for ecosystems and public health.Given this context, it is clear that methods are needed to reduce nitrate and nitrite concentrations in the cultivation system's water, with chemical and biological denitrification emerging as fundamental strategies for controlling these compounds and/or transforming them into less harmful forms.From this perspective, this review aims to address the fundamental aspects of denitrification mediated by biological and chemical processes, trends toward the integration of these two types of processes, and the main technologies used for the removal of nitrates and nitrites, to contribute to the efficient management of these potential pollutants and to the maintenance of water quality, as well as the survival of species in aquaculture systems.