Many applications involve flow in porous media and some other medium that can be separated into subdomains by a sharp interface. One example is coupled surface and subsurface flow. Simulating such applications poses several practical challenges such as, e.g., the condition number of the monolithic linear system of equations or the use of different mesh sizes in the different subdomains. We investigate a coupling using a partitioned coupling scheme using the open-source library preCICE (https://www.precice.org/) avoiding the typical problems of monolithic couplings. It follows a black-box approach which allows for a simple coupling of different disretizations or even different software packages for the subproblems while avoiding the ill-conditioning of a monolithic approach.