Any ideas what this is?

[Fballer4310]

Saw this on my rock last night. It's a bunch of string looking tubes. Nothing seems to be coming out of it and I haven't added any new rock in a long time. Thanks.

 

[bribo12]

Sponge it looks like

 

[Fishman007]

+ 1 sponge

 

[Fballer4310]

So it's harmless?

 

[bribo12]

Ya just a harmless filter feeder

 

[Fishman007]

So it's harmless?

Yep, it may spread in the right conditions. I have hundreds maybe thousands throughout my tanks. They also come in different colors, i have white like yours, red, yellow, and some chrome ones.

 

[Fballer4310]

Cool thanks for the info