Thanks Grace! The Aqua Smarte is a mineral/chlorine system. You buy a mineral reservoir that stays in the cycler for the season and you add "Bac Pacs" which is chlorine tabs inside a cylinder thingie that sits inside of the mineral reservoir (expensive little boogers!). I am going through about 1 a week and have already spent well over $300.00 for my chemicals (and I am almost out!!)