What are these??

[Bladeb126]

Weird clear tube like things sticking on my rocks, no idea what these could be

 

[blaxsun]

Those are interesting rocks...

 

[Bladeb126]

Those are interesting rocks...

Organ pipe coral skeleton. I’m reading that those white things are sponges of some sort but I’d like to get confirmation on that

 

[Clarkjw2002]

Yep, sponges.

 

[bnord]

Yep
Little sponges intertwined with organ pipe coral skeleton. Good filtration system