Scape Dechlorination (500ml) is a product one needs when you make use of tap water to fill up your aquarium. A fill up can be in the very beginning when you set up a tank. It can also be when you do weekly water changes. One squirt (approximately 1ml) of Scape Dechlorination will remove all chlorine and chloramines from 50L of tap water. If you add tap water directly to the aquarium before treating the water, you should add 1 squirt per 50L of your entire aquarium volume.