Effect of tank background colour on the hatchability of O. niloticus eggs and survival of fry

Abstract

This study was conducted at University of Eldoret, Fisheries and Aquatic Science Department hatchery to investigate the effects of tank background colour on the hatching and survival performance of Nile tilapia (Oreochromis niloticus) fry in glass tanks. The experimental set up consisted of four treatments of blue, green, red and colourless tank backgrounds where 55 fertilized Oreochromis niloticus eggs were obtained and incubated. Tanks were closely monitored, cleaned with controlled feeding once the fish were at the swim up fry stage. The best hatching and survival performance was achieved in the blue background tank. Percentage hatching of the fish was not significantly affected (p > 0.05) by the tank background colour with fish reared in blue background showing the highest percent hatching (93.62+6.06). Survival was significantly higher (p < 0.05) by the tank that had background colour with highest survival in the blue tanks (86.36+8.49). The results from the present study clearly suggest that O. niloticus fry should be reared in blue backgrounds and the use of red tanks should be avoided.