In a recent table-top experiment we demonstrated the compatibility of three advanced interferometer techniques for gravitational wave detection, namely power-recycling, detuned signal-recycling and squeezed field injection. The interferometers signal to noise ratio was improved by up to 2.8 dB beyond the coherent states shot-noise. This value was mainly limited by optical losses on the squeezed field. We present a detailed analysis of the optical losses of in our experiment and provide an estimation of the possible nonclassical performance of a future squeezed field enhanced GEO600 detector.