Contains a First Aid Cartridge (which is used in place of your filter cartridge for one week), water treatment sachets, cleaning pad and instructions.Treats most common aquarium fish problems arising from bacterial, fungal or external parasitic infections in all biOrb aquariums. Always treat as soon as symptoms appear--such as obvious fish stress, wounds and ulcers, white spot or gill and skin parasitic attacks. Not suitable for marine aquariums. NOTE: It's best to have this product on hand in anticipation of an illness. If you order this product after a problem occurs, it'll probably be too late.