In the present study, several static and dynamic intelligent computing methods, including Gene Expression Programming (GEP), newly approach of Robusted/ Least Squares Support Vector Machines (RO/LS-SVM) with Grid search and radial basic functions, robust LS-SVM with grid search, Focused Time Delay Neural Network (FTDNN) with Levenberg-Marquardt Learning Algorithm, FTDNN with Bayesian regularization Learning Algorithm, and FTDNN with Broyden-Fletcher-Goldfarb-Shanno (BFGS) Learning Algorithm have been used to estimate Acidity and Total dissolved solids (TDS) from the dissolved air flotation (DAF) unit. Furthermore, static and dynamic models perform differently under the conditions of shock loads accompanied by the temporal impact of past data on the system. Moreover, four related variables, such as COD, pH, Turbidity, and TDS from the effluent of the equalization tank (E. tank), were selected as inputs of the models, collected in an 8-hour monitoring during a year. The results demonstrated that GEP and FTDNN (with Bayesian regularization) with static and dynamic conditions modeled TDS and
pH parameters as the best results, respectively. The statistical quality of these models was found to be significant due to their high correlation between the experimental and observed chemical values, although some points in modeling, such as the implication of time lags, showed greater potential in model prediction along with simplicity and efficiency in a variety of complex physical, chemical, and biological processes.