What ARE these?!


Reefing newb
I've been seeing these puffy little oblong-shaped things in my aquarium for over a month now. They are white in color with a grayish/purplish tint. I thought it was just a few of them because they blended in with the LR, but upon closer inspection this afternoon, there's a TON of them! I guess they're multiplying? I took a scalpel and tried to scrape one off the rock. It seemed soft, and when I tried to scrape it off the rock, I ripped it open and it looked like it released a bunch of little specks (spores, maybe?). Does anyone know what they are?!

The majority of my corals turned white a month ago, and, while they aren't getting worse, they haven't gotten any better. Are these things related??