Antychlor is a water conditioner used for tap water treatment recommended for use when setting up and carrying out each water change of an aquarium. It is specifically suited to susceptible invertebrate cultivation (e.g. shrimps and crayfish). Active ingredients – sodium thiosulfate and EDTA K₂Mg – neutralize free chlorine by transforming it into harmless chlorides and bind harmful ions of heavy metals among others zinc (Zn), lead (Pb), nickel (Ni) and cadmium (Cd). The conditioner stops the action of Activchlor.