We report that the previously reported square lattice coordination network [Ni(4,4'-bipyridine)2(NCS)2]n, sql-1-Ni-NCS, undergoes acetylene induced switching between closed (nonporous) and open (porous) phases. The resulting stepped sorption isotherms exhibit temperature controlled steps, consistent high uptake and benchmark working capacity (185 cm-3 g-1 or 189 cm-3, 1-3.2 bar, 288 K) for acetylene storage.