MAGIX is a planned experiment that will be implemented at the upcoming accelerator MESA in Mainz. Due to its location in the energy-recovering lane of the accelerator beam-currents up to 1mA with a maximum energy of 105 MeV will be available for precision experiments. MAGIX itself consists of a jet-target and two magnetic spectrometers. Inside the spectrometers GEM-based detectors will be used in the focal plane for track reconstruction. The design goals for the detector modules are a spatial resolution of 50 um, a size of 1.20 m x 0.3 m and a minimal material budget. To accomplish these goals we started developing several GEM-prototypes to study different behaviors and techniques to optimize the final detector design. The GEM foils used are provided by CERN and are trained, stretched and framed in our laboratory. The readout is done with an SRS based system. In this contribution the requirements, achievements and the ongoing developments are presented.