To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie 1 Video of a goldring surgeonfish, Ctenochaetus strigosus, swimming in a bidirectional oscillatory flow with an average velocity of 3.0 BL s-1 (peak velocity of 4.7 BL s-1) and a frequency of 0.3 Hz. Swimming in unsteady water flows: is turning in a changing flow an energetically expensive endeavor for fish? Mathias Schakmann, John F. Steffensen, Peter G. Bushnell, and Keith E. Korsmeyer Journal of Experimental Biology 2020. 223:None-None; doi: 10.1242/jeb.212795 Download Original Video