If you are using the easy Frog @ease sanitizing system in your hot tub then you are going to need the Jumpstart shock packet once a month when you change your Smartclor chlorine cartridges.
This jumpstart packet uses 1.5oz of specially formulated granular chlorine to great a reserve bank of chlorine. Once this bank is established the Frog Smartclor cartridge automatically regulates the chlorine level based on your usage.