The Demcon convergence Membrane Fouling Simulator (MFS) was developed to evaluate the biofouling growth on membranes. The unit comes with a small cell and spacer for flat-sheet membranes. The system measures the pressure drop over the membrane over time at a constant flow and pressure which will increase throughout the experiment because biofouling growth constricts the flow path. The MFS is an easy and reliable way to compare and evaluate the biofouling potential of different feeds, membrane materials and membrane/spacer configurations.