la zeolite certamente non toglie ammoniaca in acqua salata. Si usa in acqua dolce per quello scopo e si rigenera mettendola in acqua salata, perchč il sodio toglie l'ammoniaca dalla zeolite.
http://reefkeeping.com/issues/2007-02/rhf/
Few filter media are capable of binding ammonia from seawater. The zeolite clinoptilolite (a sodium aluminosilicate) is capable of binding ammonia from freshwater, but the sodium ions in seawater displace much of the ammonia. In fact, the ammonia binding capacity of clinoptilolite in freshwater can be regenerated by rinsing it with salty water. Consequently, its capacity to bind ammonia in seawater is very low, if any, so it is not a very useful product for marine systems.