Strange yellow thing in tank

[LittleFishiez]

I got some new live rock for my tank the other day and this thing is on it. I have no idea what this but it moves very slowly. Anyone have any ideas?


Sent from my iPhone using Aquarium Advice

 

[Autumnsky]

It looks like a sponge from the pic. Does it move like a slug?

 

[Marty.h]

Looks like a pineapple sponge to me a harmless filter feeder

 

[Finnster]

I concur with Autumnsky, it looks like a sponge. Like he said, tell us if it moves!

 

[Marty.h]

Pineapple sponges can move they have like long strings come of them which anchor them in place I have some in mine

 

[Finnster]

Cool! That's neat!