Abstract

• Aquaponics integrates aquaculture and hydroponics into a common closed-loop eco-culture where a symbiotic relationship is created in which water and nutrients are recirculated and reused, concomitantly fully utilized and conserved. In this study, GIFT Tilapia (Oerochromis niloticus) (2.8 ± 0.5g) collected from Hlawga Hatchery Station; Yangon which was cultured with different feeding frequency in DWC aquaponics systems to investigate the appropriate feeding frequency for optimal growth of GIFT tilapia. These experiments were divided into three treatments on the basis of feeding frequency (2 times (2T), 3 times (3T) and 4 times (4T)) per day respectively, having three replications. Then 24 seedlings of lettuce were introduced aquaponic system. Fish were fed floating pellet for 5 % of body weight. Fish were cultured from July to November, 2022. The highest total mean weight was found in 4T (356 g), followed by 3T (326 g) and 2T (281.6 g) respectively. The highest final weight gains were recorded in 4T (219.6 g) while the lowest weight gain in 3T (186 g) followed by 2T (161 g) in the end of experiment. In November, the highest FCR was found in 2T (1.1) while the lowest FCR was recorded in 4T (0.9) followed by 3T (1). High specific growth rate (11) was found in 4T treatment in two production cycles. For plant quality index, the highest number of grade A plants were observed in 4T. However, 12 and 13, Grade B plants were found in 2T, 3T and 4T in first and second harvest times. According to this study, it is understood that feeding frequency has an important effect on growth rate: 4T system shows the most favorable outcome for tilapia and lettuce than other frequencies.