Found the info now
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[FONT=Arial, Helvetica, sans-serif]AmQuel+ is compatible to use with all water quality test kits except for the ammonia test kit that uses Nessler reagents that read in shades of amber or yellow, and the oxygen test kit that uses Winkler reagents. Residual AmQuel+ and its reaction products are incompatible with the Nessler-and Winkler type reagents, resulting in false, high ammonia and low oxygen concentration readings. Ammonia test kits using salicylate-type reagents are appropriate for accurate test results. Excellent examples of high quality salicylate test kits with technical grade reagents are Kordon's AquaTru Test Kit #35970 for salt water and #35980 for fresh water. Any oxygen test kit other than those using Winkler's method is compatible with AmQuel+. "[/FONT]