What is this? Something on glass...

[thirty5]

Can anyone help me out with ID of this. There are a couple of them in this spot. I have never seen it before.

 

[thirty6]

is that on the glass or coming a rock or are you talking about the spiral looking things next to bigger white mass

 

[thirty5]

is that on the glass or coming a rock or are you talking about the spiral looking things next to bigger white mass

The thing in the middle the biggest thing in the pic. It is on the glass. It seems to have a tube coming out of it sort of...

 

[dnov99]

Looks like the backside view of a tunicate. Guessing its in your sump?? Its harmless and beneficial...

 

[thirty5]

I just googled it, it looks like you may be right. They are actually in my display on the glass behind rock.

 

[rookie07]

Id say sponge.
They will do that.