Review on Tetra AquaSafe tap water treatment agent, 5 l by Gabriela Strzeek ᠌

There is an error in the description of the product in the section: Mode of application 5 ml for every 10 liters of aquarium water On the label: 5 ml for every 10 liters of new tap water directly into the aquarium These are very different things, since you are changing, most likely 25% of the water, and you need to calculate by the volume of water changed, and not by the volume of the aquarium.