Tap water treatment agent for the immediate treatment of aggressive tap water into fish-friendly and natural aquarium water - with BioExtract formula for healthy and clear water the new formula promotes healthy water and healthy fish through a unique mix of natural biopolymers and trace elements Ingredients in tap water that are harmful to fish are immediately neutralized: chlorine is eliminated and heavy metals such as copper, zinc and lead are completely and permanently bound with BioExtract formula: natural biopolymers support the growth of beneficial bacteria - for healthy and clear water suitable for fresh and salt water aquariums