Hello! I'm really new to the Forum, just joined a few minutes ago. I hae a 25,000 gallon in ground SWG pool. Have been dependent on pool supply stores for chemical analysis and advice. I think I've gotten shafted more than once that way. Really interested in getting to know more about pool chemistry. I'm a do it yourselfer, have installed replacements for both pumps and a new SWG since acquiring this, my first and only pool (Actually, it seems to be more like a pool with an attached house).