I.D. please.

[Daddynemo30]

I'm being told it might be pineapple sponge. Im not against having natural pieces in the tank that I didnt place there, but I really wanna figure out how to be sure. They are little white tentacle shapes coming out of the rock. They dont move at all, dont move when touched, and have like a stiff gel type texture. Anyone able to help? In the pic they are off center to the lower right. On this rock they seem tobe a cluster. On others, they are all independent and look kinda like a Cyprus root

 

[WV Reefer]

I'm being told it might be pineapple sponge. Im not against having natural pieces in the tank that I didnt place there, but I really wanna figure out how to be sure. They are little white tentacle shapes coming out of the rock. They dont move at all, dont move when touched, and have like a stiff gel type texture. Anyone able to help? In the pic they are off center to the lower right. On this rock they seem tobe a cluster. On others, they are all independent and look kinda like a Cyprus root

Spaghetti Sponge.