White Spot is a parasite infection, the white spot is a cyst in which the adult parasite develops. Anti White Spot destroys the free-swimming stage of the white spot life cycle. As this is the only stage of the life cycle affected by the treatment the product remains active for several days, ensuring the free-swimming parasites are destroyed as they emerge Dosage: 1 ml of Anti White Spot Plus treats 10L Repeat treatment after 4 days