The Water Disinfection with Different Type UV Lamp Systems on Bacterial Load in Small Scale Recirculating Aquaculture Systems

Abstract

The present study was planned with the aim of inactivating the total bacterial load and species in tilapia fish tanks kept in fresh and seawater conditions with high stock density with different UV lamp models. In this context, the UVC+UVA-Led lamp system was compared with the conventional UVC lamp system and the total bacterial load in the tanks and the inactivation effect on the bacterial species were determined. Total bacterial load on the medium and bacteria species were identified in terms of their morphological characteristics using the spread plate method. Bacteria that emerged at different times in the trial sets were identified as Edwardsiella tarda, Salmonella sp., Aeromonas hydrophila, Pantoea sp., Citrobacter youngae, Serratia ficaria and Citrobacter freundii. The total bacterial load in both freshwater and seawater environments in both lamp groups showed a decrease compared to the control group. With this, the conventional lamp model was more effective on the total bacterial load in the samples taken during the trial. Although all bacteria were inactive in both lamp groups, Serratia ficaria bacteria were not eliminated in the seawater environment. The results show that UV LEDs can be a better alternative to traditional UV mercury lamps for water disinfection.