Evaluating the effectiveness of ammonia treatment in shrimp ponds was conducted in a laboratory with two kinds of zeolites at six replicates of ammonium contents. Zeolite 2 (powder form, made in Indonesia with SiO2: 75.50 percent and Al2O3: 10.56 percent) had much more stable in processing of ammonia treatment of indoor condition compared with Zeolite 1 (particle form - made in Vietnam with SiO2: 69.50 percent
Al2O3: 15.58 percent). As NH4+ content was low, the effectiveness has a peak after the first days of the treatment period. By contrast, as NH4+ content was very high, the effectiveness could be found in the last day. These values could be reached to 72 percent after 7-treatment-days. Moreover, both zeolites play an important role in making a stable environment, stimulating the development of phytoplankton. Thus, it resulted in the increasing effectiveness of ammonium treatment indirectly.