API Ammo Lock(118ml)If your aquarium tests positive for ammonia, you are recommended to act quickly by doing a partial water change and then neutralise the ammonia. Ammmonia is toxic to fish cells, especially the gills, and so API Ammo Lock works instantly in both fresh and saltwater aquariums to detoxify ammonia and remove chlorine and chloramines. A liquid treatment that is fast, reliable and effective, API Ammo Lock locks up ammonia in a non-toxic form until it can be broken down by your tanks biological natural filter, and helps to eliminate fish stress whilst promoting healthy gill functio