I have had similar problems with my sparkling graphite.
A couple of weekends ago, I did a full detail and applied 2 layers of Chemical Guys JetSeal 109. Literally nine days later, I go to work and park near a curb that has a patch of grass. Well I come out at lunchtime, and I find a sprinkler repair truck. No problem, I'm paranoid, so i parked far away from the curb, so I'm safe. Wrong. My car is covered in water spots all the way up to my sunroof. Worse is that it was about 98 degrees and sunny. The spots were already dried.
Again, no problem, because I have that wonderful JetSeal applied, I should be pretty safe from any permanent damage to the clear coat. I'll just quick detail and clay it when I get home. Wrong again.
The first picture is how I found my car, the second is after a quick detail and clay bar treatment.
I have since spent an entire saturday with a porter cable DA polisher and you can still see the spots at certain angles. I was temped to go out and buy a rotary buffer to fix this, but then thought why bother, the crappy paint is just going to melt
the next time it gets wet anyway. I tried chemical guys water spot remover as well, and it did zilch.
I'm also really surprised that jetseal did absolutely nothing to protect me from water spots. Well, except it made the water bead, so that now I at least have uniform paint damage