Tube sponge thing

[GSnake]

Was looking for my goby today and turned my rock upside down, to see these soft jelly like tube things with holes. Almost colorless and woven into bottom of rock that stays against sand. What could it be.

 

[kichimark]

It's definitely a sponge and I am unsure on what species it is but I do know it is harmless. I have these in a few spots as well and they never became a problem.

 

[GSnake]

Good to know. Hope I get a nice orange sponge or something on the top or elsewhere. That would be interesting