Microbubble aerator test and harvest target prediction based on oxygen consumption of red tilapia (Oreochromis sp.)

This study compared the performance of microbubble aeration to conventional aeration system (blower) in increasing Dissolved Oxygen (DO) content, measure the standard oxygen transfer rate (SOTR), Standard Aeration Efficiency (SAE), and assessed the oxygen consumption of red tilapia to estimate the harvest target. The results showed that in the rate of air discharge of 3 L min-1, the microbubble aerator produced higher DO content (6.58±0.03 mg L-1) than conventional aerator (5.59±0.24 mg L-1). The increase of DO content in microbubble aeration was amounted to 2.13 mg L-1, while the DO content in conventional aeration increased 1.14 mg L-1 from the control treatment. The SOTR value from the microbubble aeration was 0.0019 kg O2 h-1 with the SAE value of 0.022 kg O2 KW-1 h-1. The values were higher than the conventional blower aeration treatment with SOTR value of 0.0007 kg O2 h-1 and SAE value of 0.0067 kg O2 KW-1 h-1. This study also assessed the DO value of recirculating aquaculture system (RAS) where the DO value produced by microbubble aeration was 7.44±0.14 mg L-1, which was significantly higher (p<0.05) than the conventional aeration (6.51±0.26 mg L-1) and the control treatment (5.35±0.06 mg L-1). The measurement of the oxygen consumption rate of fed tilapia was higher than the unfed treatment. The value of oxygen consumption rate of fish in fed treatment and the measured DO value was used to estimate the number of fish harvested in certain body weight. This study concluded that microbubble aerator produced higher DO value, increased the rate of oxygen transfer, and saved more energy compared to conventional blower aeration. The harvest target of fish cultured with microbubble aeration was 17 higher in comparison with blower aeration. © 2021, BIOFLUX SRL. All rights reserved.