Modified photoperiods and light intensities for grow-out production of nile tilapia (O. niloticus) under indoor tank culture system

Department of Agricultural and Biosystems Engineering Department, College of Engineering, Central Luzon State University, Science City of Munoz, Nueva Ecija, Philippines 3120

^* Corresponding author: mmcinense.dabe@gmail.com

Abstract

The study aimed to evaluate the effect of modified photoperiods and light intensities on grow-out production of tilapia under indoor tank culture system; specifically on water quality and on growth performance of tilapia. The study was conducted inside the greenhouse and considered two factors: photoperiod (24L:0D, 20L:4D and 16L:8D); and light intensity (40 watts m^-2, 60 watts m^-2 and 80 watts m^-2); also, a control treatment was set-up outside the greenhouse to receive the normal environmental condition. Light manipulations inside the greenhouse were able to sustain the water quality within the desirable level for tilapia cultured in tank; while control tanks shows high water quality variation. Growth performance of tilapia cultured in tank responds positively in prolonged photoperiod at different light intensities. However, light manipulation gave insignificant difference on feed conversion ratio and survival rate compared to normal condition. Results indicated that 20-hours photoperiod and 40 watts m^-2 light intensity is just enough to sustain the recommended water quality and better growth performance of the cultured tilapia in indoor tank system. It can be concluded that longer photoperiod and restrained light intensity can improved the growth performance of tilapia under indoor tank culture.