JJ is giving you some info regarding runtime and SWG results, but runtime is more for pool filtering and skimming and cleaning. You need to satisfy those first, then if that's also enough runtime for your SWG, then you're good. If not, then you up runtime until you have enough hours to produce the chlorine your pool requires. It's a little daunting, because there are a lot of variables and no two pools have the same set of variables, which is why there is no hard and fast formula (as the pool store would have you believe). You just have to fool with both runtime and SWG % until you get it right. And it also gets a bit trickier because the variables change with the seasons. So your runtime and SWG % will be different for different times of the year. That's what Dude meant by "20/40/60/40/20" (see post #4). That's how his SWG % changes throughout his swim season. Mine is different, but has a similar curve. And we got those numbers through a year or two of trial and error. But eventually we (and you) figure these numbers out. And while you'll continue to adjust these number a bit indefinitely, you'll eventually have this starting point basis that will make this task easier.
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