White Waspy nest looking thing?

[harthag12]

Set my tank up a few months ago with live rock from KP Aquatics. I love this stuff. I keep finding new things when I look. I've found 2 crabs, a snail, bristleworms, featherdusters galore, sponges, most recently a fairly large pencil urchin who I don't know how I haven't seen it but this new thing has me stumped. It showed up 2 days ago; it sways in the water column but I have no clue what it is. I think another one formed on top of a rock today and it has an almost snail shape to it but it's cocoonyyy looking. Only livestock I've added to the tank are 2 clowns & 1 Black Molly who had babies, I have 2 living in the back of the all in one. Need help on this one.

 

[saltyhog]

Maybe some kind of sponge?

 

[Katrina71]

Looks like it to me too

 

[Idaho Mojo]

Looks like a tunicate to me with how uniform the holes are

 

[Hemmdog]

Around the hole is branching hydroids.

 

[harthag12]

Thanks, it stayed that way for 2-3 days and than basically deflated. I think it's still there but it's basically a flat line now. I thought I saw another one form for a day or two in another part of the tank as well. This rock is full of surprises. Found what I believe is a Chiton as well now.