Understanding Water Quality Dynamics in Aquaculture Ponds in Sunyani, Ghana: Insights from Partial Least Squares (PLS) - Path Modeling JFAR Understanding Water Quality Dynamics in Aquaculture Ponds in Sunyani, Ghana: Insights from Partial Least Squares (PLS) - Path Modeling Nicole E.G Otoo 1* , Peter O. Sanful 2 , Wahab A. Iddrisu 3 , Solomon Amfoh 4 , Okyere K. Boateng 5 1,2,4 Department of Fisheries and Water Resources, University of Energy and Natural Resources, P. O Box 214, Sunyani, Brong Ahafo Region, Ghana 3 Department of Mathematics and Statistics, University of Energy and Natural Resources, P. O Box 214, Sunyani, Brong Ahafo Region, Ghana 5 Fisheries Commission, Sunyani Knowledge of water quality in aquaculture ponds in Ghana is limited due to lack of qualitative and quantitative field data. We conducted detailed field measurements to assess the effect of hydrographic and production factors on water quality. Ponds cultured with Nile tilapia Oreochromis niloticus, and African catfish Clarias gariepinus, were selected for the study. Eleven fish ponds with stock ranging between 7-21 days were randomly selected and sampled at monthly intervals for five months, with the aim of capturing water quality patterns through a full production cycle. Seventeen parameters were measured and analyzed using Partial Least Squares (PLS) - Path Modeling. Most ponds had unusually shallow depths, characterized by excessive stocking densities of 200% on average above recommended rates. This necessitates high feeding rates, thereby reducing the assimilative capacity of ponds. The effect of feeding intensity on water quality increased with stock age. Persistent algal blooms, low DO, high temperatures and elevated levels of ammonia, nitrite, phosphate, TDS and conductivity were indicative of generally poor water quality. The model showed that 82 % variability in water quality was due to production inputs. Standard stocking rates, feeding rates and construction of deeper ponds are recommended. Keywords: water quality, aquaculture ponds, hydrographic factors, path model, tilapia (Oreochromis niloticus), catfish (Clarias gariepinus), Sunyani INTRODUCTION The maintenance of good water quality in a pond culture system is critical for the success of raising fish to meet various human needs (Devi, 2013). Good water quality supports the efficient growth and survival of culture species and promotes good fish health, reduces stress, improves growth performance, increases productivity and reduces environmental impacts (Boyd and Tucker 1998; Parven et al., 2013). Poor water quality however, may be detrimental to fish health through increased susceptibility to stress, disease and mortality, and may also have serious environmental consequences (Boyd, 2017). Furthermore, susceptibility to infectious diseases by fish is heightened by deterioration in water quality (Boyd, 2017). Thus, poor fish growth and reduced reproductive performance often is a consequence of poor water quality (Keremah et al., 2014). The ability of fish to maintain optimum growth and reproductive performance is dependent largely on the water quality characteristics of the aquatic medium in which they live (Devi, 2013). Water quality therefore is a major constraint to the success of aquaculture operations and affects the quality of aquaculture products and its suitability for human consumption (Boyd and Tucker, 1998). The knowledge and application of good water quality management principles by aquaculturists in culture systems will help meet the increasing demand for safe and quality fisheries products (Boyd and Tucker 1998). *Corresponding Author: Nicole E.G Otoo; Department of Fisheries and Water Resources, University of Energy and Natural Resources, P. O Box 214, Sunyani, Brong Ahafo Region, Ghana. Email: nicole.otoo.stu@uenr.edu.gh Tel: +233541890481 Research Article Vol. 4(1), pp. 028-042, August, 2019. © www.premierpublishers.org, ISSN: 9901-8810 Journal of Fisheries and Aquaculture Research