Hydroids?

[TnFishwater98]

Are these Hydroids?

 

[Goaway]

Most likely, dwarf angels eat those, sometimes. or you can use tweezers to remove them. Really have to get down in the rock though.. Unless it's some kind of weird algae...

 

[TnFishwater98]

Most likely, dwarf angels eat those, sometimes. or you can use tweezers to remove them. Really have to get down in the rock though.. Unless it's some kind of weird algae...

Is that only way to remove. Not wirried about this piece of dead coral on top of frag plug. I can remove that but I see some Similar looking strings on a couple of other pieces

 

[TnFishwater98]

Any Unnatural way to clear these off frags?

 

[TnFishwater98]

Are these Hydroids?

Bumping my own post but just got a possible identification at my LFS.
They were taking back by it but have suggested it’s a sponge. I hadn’t thought about that but I believe they are right. Can anyone else confirm this? Best way to keep in check?