The tolerance of salinity and hardness was checked on the growth and survival of Nile tilapia (Oreochromis niloticus) in National Agriculture Research Council (NARC) Islamabad. Fry of the Tilapia measuring between 2.5cm to 2.9cm in total length and weighing between 0.435g to 0.603g (Body Weight BW) were used for the salinity and hardness treatment. Different levels of salinity from 0-15ppt were developed for the three months. 100 % survival rate was observed in 0-7.5ppt while in 12.5ppt and 15ppt all the fish died. Salinities between 0-10ppt were endured by the fish however the most appropriate salinity level was 5ppt on which maximum growth was recorded. For hardness treatment different concentrations of 350mg/lit, 450mg/lit, 550mg/lit and 650mg/lit of CaCl2 were used. No mortality was observed in this case and the most preferred concentration on which the fish showed maximum growth was 550 mg/lit.
Keywords: Growth Performance, Survival, Water Quality, saline resistance, tilapia growth
