A recent study in Thailand assessed three densities (20,25,50 fish/m3) of sex-reversed male Nile tilapia (Oreochromis niloticus) in integrated multi-trophic and water-recirculating aquaculture systems (IMRASs). A paper on the results of the study, published in the scientific journal Sustainability, reports that the fish that put on the most weight were cultivated at the highest density in the IMRAS.
Maintaining a good ecological balance amongst several living organisms such as phytoplankton, zooplankton, different types of fish and shellfish, and aquatic plants was key.
“The results indicated,” says the report on the study, “that, by providing proper interdependency between various species of living organisms, the concentrations of ammonia, nitrite, and phosphate in the system were maintained below dangerous levels for Nile tilapia, throughout the cultivation period.”
Aquatic plants in the treatment tank were able to take up the unwanted nitrogen and phosphorus – the compounds with the highest removal efficiencies with uptakes of 9.52% and 11.4%, respectively.
“This work demonstrates the success of the implementation of a closed-loop aquaculture system where a treatment tank is introduced,” concludes the report.
– Quentin Dodd