ANALYSIS OF THE EFFECT OF WATER QUALITY ON THE GROWTH OF NIRWANA tilapia (Oreochromis sp.) AT THE NATIONAL INSTITUTE OF FISHERIES AND AQUACULTURE, MAUBARA, LIQUIÇA, TIMOR-LESTE

National Institute of Fisheries and Aquaculture (NIFA) is the first national institute of fisheries and aquaculture in Timor-Leste which was established in 2016 and operated in February 2018, since operating in 2018 until 2021, the NIFA has distributed total fish fry 244,313 tilapia to 336 fish farm groups and communities (individuals) in 12 Municipalities. One of the supporting factors in the success of tilapia cultivation is the availability of feed beside of feed the availability of water quality (temperature, DO, pH) also one of the factors that will determine the success of fish farming. The quality of water in fish ponds must be managed properly so that its growth remains optimal. This study aims to determine the correlation between the quality of the aquatic environment (parameters of temperature, pH, DO) on the growth pattern of tilapia. This research was conducted at the end of April to the end of June 2022. The method used is insistu data collection, water quality sampling and random sampling on fish measurements. The results showed that the quality of the aquatic environment had a close relationship on growths of Nile tilapia, where temperature, pH, dissolved oxygen on the absolute length of tilapia had a positive correlation value (r) (temp to length = +0,593; pH to length = +0,693; dissolved oxygen to length +0,786), while parameters pH, dissolved oxygen on absolute weight of Nile tilapia had a positive correlation value (pH to weight +0,161; DO to weight +0,519), parameters temperature and weight body absolute value of tilapia has a negative correlation value (temp to weight -0,004). Growth pattern of fish in this study is negative allometric where the growth of fish length is faster than the growth of Nile tilapia weight with the t-test Tcount>Ttable. Keywords: Water Quality, Growth Tipalia, National Institute of Fisheries and Aquaculture