Just so it's said: you don't add salt for at least a month. I filled my pool about this time of year, and didn't add salt until Spring. My SWG wouldn't have worked in the winter anyway, so I figured if waiting to put in salt for a month is good, waiting until spring would be even better. I ran my pool as a non-swg pool during that first winter, using liquid chlorine. Then fired up the SWG when temps warmed up.