Hi. First post on here. I have a SWG (all Pentair equipment). I'm getting this substance showing up on the floor of my baja shelf and my attached hot tub. At first I thought maybe it was some kind of white algae but now I'm getting a lot more of it and it looks like salt so I'm really confused. I even rubbed it with my finger and it feels like grains of salt... but the salt would dissolve, so then I'm wondering is it calcium... but my calcium levels are around 250 so I'm very confused. Thanks for the help.