Geosmin and Methyl-Isoborneol (MIB) are naturally occurring compounds commonly found in fish in RAS (Recirculating Aquaculture Systems) production. Both substances accumulate in the fat tissue of the fish and lead to a muddy earthy taste of the fish. Every year this leads to high economic losses for the aquaculture industry caused by prolonged production times due to the need to off-flavor the fish in purge tanks and further by the rejection of produce by the fish refining companies.
As of today, the usual method to remove geosmin from the fish is by placing them into large high purity water tanks that are rich in oxygen. However, this is a relatively costly method to ensure proper removal, as large quantities of pure water are required. ULTRAAQUA UV research department has first-hand experience in solving and documenting geosmin control.
The most optimal strategy in removing geosmin is to avoid or minimize the concentration of geosmin in the culture tanks and thus minimizing the need for off-flavoring in the purge tanks further on. ULTRAAQUA UV experts will assist in optimizing plant layout and management strategies to reduce geosmin formation. In addition, ULTRAAQUA UV offers equipment to remove accumulated geosmin. The optimal solution typically varies from site to site depending on local characteristics.
Often the optimal solution involves ULTRAAQUA AOP systems for combined chemical oxidation and photolysis breakdown. It is important to note that each case is sensitive and different requiring close investigation due to RAS intenseness, the multiple processes involved, and variation in overall farm management.