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Tilapia studies in Iran were begun since 2008 and different aspects of tilapia aquaculture in are researched. In the present study, limnologic factors of indoor and outdoor tilapia culture ponds, also growth performance of the cultured tilapia were investigated at the National Research Center of Saline Water Aquatics, during the culture period of 2016. Water temperature, dissolved oxygen, pH, salinity and ammonium concentration were measured. Depth of water transparency, the composition and frequency of plankton and macro benthos of the earth ponds were studied. Total length and weight of fish were measured to evaluate growth performance. In the earth ponds, the ranges of minimum and maximum of water temperature were 16.6-27.5°C and 20.5-31°C. The range of dissolved oxygen was 2.11-10.19mg/l in the morning and 7.06-14.64mg/l in the afternoon. PH was recorded 8.97-10.9 in the morning and 9.04-11.00 in the afternoon. The depth of the water transparency was 40- 105 cm. Water salinity was 7.94-8.82 ppt. The concentration of NH4+ changed from less than 0.05 to 0.4 mg/l. The frequency of phytoplankton and zooplankton was 2050-2848 and 269-101 per liter, respectively. The dominant phytoplankton and zooplankton were chlorophytes, diatoms and rotifers. The abundance of macrobenthos was 3467-558/m 2 and the dominant group were chironomids. Pearson 2-tailed correlation between the amounts of factors including temperature, salinity, dissolved oxygen, pH, NH4+ , length and weight of farmed fish in earth ponds showed a direct significant correlation between pH value against ammonium concentration, and total length against body weight of the fish, also between pH against water temperature and total length of the fish. There was a reversed significant correlation between the dissolved oxygen against water temperature and pH (p |
