What type of encrusting worm?

[BubblesandSqueak]

So my Astrea snail has an encrusting worm in the shape of an infinity symbol. A emerald crab eats it and it keeps growing back. This snail literally does nothing in the tank nor does the other Astrea so I’m not fond of them. They do not travel more than 3” square. Is this even worth keeping for the issue? What type of worm is it?

 

[Idoc]

Possibly a vermatid snail on his shell.

Just take him out of the tank, crush the encrusting hitchhiker's shell with plyers. Then put the Astraea back in the tank.

 

[WheatToast]

Do you have clearer photos?

 

[BubblesandSqueak]

Do you have clearer photos?

The blues just came on but looks clearer.