I just read a post by Waterbear about iron stains and salt. My builder used Morton table salt-550 lbs of it. Would that have any effect? The bags, as I recall, said 99.6% pure. Could that also cause what looks like rusting of screws in the water? My builder came by and replaced some screws but cleaned off some with pH down and left me the bag for future leaning.
It is not slimy, but gritty.
How do I get rid of the metals in the pool if that is the cause?