I have no clue what it is. I would just take it out and get that crap off
Edit: looks like te fungus stuff that appears around a dead fish if it is not taken out of the tank.
Thanks, yeah it looks like some spiderwebby stuff idk.
Should I boil it?
I believe it is a type of fungus that often grows on new DW. You could just let it go; whatever it is feeding on will be exhausted and it should die off. This may take a while. You could also remove the DW and scrub (or boil) it to remove the fungus. It may grow back or it may not. This is normal.