A relaxed eddy accumulation flux measuring system coupled with ion chromatographs (REA-IC) was developed and optimized to capture the flux of ammonia and other water-soluble gases. The instrument assembly is based on the ambient ion monitoring ion chromatographs (AIM-IC) adapted following previous work in the group. The REA-IC system uses wet parallel plate denuders to capture water-soluble gases, namely NH₃, HNO₃, HONO, HCl, and SO₂ followed by automated IC analysis every hour. The system is designed to have a continuous gas flow by operating the conditional sampling between ambient air and a clear air source. The fast-response valves of the conditional sampling, located on the clean air stream, are controlled according to vertical wind direction to separate updrafts and downdrafts. Accurate flux measurements using this technique require excellent precision between the respective reservoirs. Our preliminary estimates based on REA simulations that are informed by eddy covariance NH₃ fluxes over maize crops following fertilization show maximum fluxes of ~50 umol m^-2 h^-1 leads to a concentration difference of less than 30% between the two reservoirs, emphasizing the need for high measurement precision. Preliminary lab tests showed a relative precision of ~10 % for NH₃ and HONO concentrations measured in both up and downdraft reservoirs, with SO₂ concentrations being close to the detection limit that precision was impeded. Normalization based on a lithium bromide (LiBr) internal standard made an improvement on the precision. The use of LiBr also facilitates diagnosis of the instrumentation and background influence of the denuder assemblies. The REA-IC system was deployed in a corn field (Ottawa, ON) with its inlet close to a sonic anemometer (CSAT-3, CSI, Logan, UT), which was connected to a data acquisition and control flux measuring system developed by Agriculture and Agri-Foods Canada. The REA sample software controlled the fast-response valves and processed the standard deviation of the vertical wind speed and the REA coefficient using water vapor as a surrogate. The hourly ammonia fluxes were calculated using the REA technique as the concentration difference between up- and downdraft reservoirs. The performance of the REA-IC measuring system will be presented. The ability to resolve NH₃ fluxes can help assess the utility of different agricultural management practices.