To preserve the aquatic environment from overfishing, aquaculture has rapidly developed over the last years, becoming an important industrial section. To keep the bacterial load in fish farms to a low level, UV disinfection is needed. When turbidity is increased, ozonation prior to UV radiation is highly recommended. Ozonation in fish farming facilities is beneficial as the oxygen concentration is enhanced when ozone reverts to oxygen.
The treatment with UV and/or ozone is widely used as the physical characteristics of the treated water are not affected so water disinfection occurs without undesirable side effects e.g. toxic by-products, pH changes or temperature fluctuations. Thus, the improved water quality, will possible increase stock density and reduce significantly the risk of disease. Aquacultures are located in remote facilities where the energy consumption is critical, and therefore amalgam lamps are usually used.