I had a pool company come out and open my pool as this was the first opening and i didn't feel comfortable doing it myself. i unfortunately was not able to make it home to watch them do it- so here are my questions. They opened Wednesday and when I checked the chlorine o nThursday, it was zero??? Shouldn't it have been around 3 ppm? The pool smelled of chlorine, which I found odd, but there was none when I checked. Also, the polaris has been collecting a ton of what looks to be salt in the bottom of the pool. I have a SWG, but opened the pool as chlorine untilt he weather warms up. can someone help me understand what this might be?