If the aquarium tests positive for ammonia, act quickly by doing a partial water change and then neutralize the ammonia. Ammonia is toxic to fish cells, especially the gills. AMMO-LOCK is a liquid treatment proven to protect fish cells from ammonia. AMMO-LOCK works instantly, in both fresh and saltwater aquariums, to detoxify ammonia and remove chlorine and chloramines. AMMO-LOCK locks up ammonia in a non-toxic form until it can be broken down by the tank’s natural biological filter. Eliminates fish stress and promotes healthy gill function.