A gas-liquid separator system for a fuel cell, the system comprising: a coalescer apparatus, the coalescer apparatus comprising: an opening arranged to receive a flow of fluid; an array of screens arranged substantially parallel to the direction of fluid flow, wherein the screens are attached at each of their ends opposite the opening to an impermeable surface such that fluid is prevented from flowing through the impermeable surface and is directed through the screens; the system further comprising a reservoir for containing gas and liquid phases of the fluid, wherein the reservoir is arranged to receive fluid from the coalescer apparatus.