Correlation of Water Quality Parameters in a Recirculating Aquaculture System for the Nile Tilapia (Oreochromis niloticus) Cultivation

The Nile tilapia (Oreochromis niloticus) is widely favored for its high nutritional value, which offers health benefits for human consumption. Aquaculture practices are commonly employed to meet growing consumer demand. One effective method is the Recirculating Aquaculture System (RAS), known for its efficient water use, waste management, and stable water quality. However, maintaining water quality remains a key challenge due to residual feed, fish waste, and environmental influences. This study examined the correlations among various water quality parameters within a RAS specifically used for the Nile tilapia cultivation. Maintaining optimal water conditions ensures fish health and maximizes production efficiency. The parameters assessed in this research include temperature, pH, dissolved oxygen (DO), and ammonia (NH₃). The RAS setup consisted of fiber filters, pumice, activated charcoal, and bioballs, operating with a single grow-out tank for the Nile tilapia.  Over a 42-day monitoring period, data collection was weekly carried out. Based on results, a strong positive correlation between pH and ammonia was recorded in the culture pond (r= 0.72). Negative correlations were observed between temperature and ammonia (r = –0.31) and temperature and pH (r = –0.30). No significant correlation was found between DO and pH (r = 0.34). These findings indicate that while the RAS helps stabilize water quality, the interactions between parameters still influence system performance and fish health. Proper monitoring and management of these parameters are essential to support optimal Nile tilapia RAS farming production.