2 Spare charcoal flywheels suitable for ASAP filters.
They are made of carefully selected puffball saturated with activated carbon. They effectively eliminate all chemical contaminants. Their installation is recommended in new aquariums, for tanks with fish that have undergone medical treatment (in order to remove drug residues from the water) in case of water poisoning or coloration (caused by pieces of wood or roots placed in the tank). After 2-3 weeks of use, the sponge should be removed as by then it may start to release previously absorbed substances back into the water.
