We present results of a hydraulic pre-study, conducted prior to an ecohydraulic experiment. The ecohydraulic experiment focusses on the effect of turbulent flow properties on fish passage success in a vertical slot. We aim to investigate if turbulent fluctuations may increase passage success of small fish compared to flow with low turbulence. In the hydraulic pre-study we develop and analyze different technical designs in order to provide realistic turbulent conditions for the ecohydraulic experiments. As a reference, we use results of in-situ ADV-measurements obtained in a vertical slot fishway at Koblenz, Moselle River in Germany. PIV measurements are carried out in a scale model of the ecohydraulic flume and show that similarity of turbulent flow in the slot region may be obtained by a sufficient level of upstream turbulence generated by an adjustable device of rotatable fins. Turbulent kinetic energy distribution and energy spectra of longitudinal and lateral velocity components match well supporting our conclusion that realistic turbulent flow may be provided using the rotatable fins.