Need ID of micro critter

[ReeferAl]

I'm looking for an ID of a tiny creature I found attached to the underside of a PVC ring in my coral QT. I posted in the general forum, but someone suggested posting my question here. Since it is photo-intense I'm posting a link instead of repeating all the photos. Here is the thread.
I'll post just one of the photos here as a preview:

Thanks.

Allen

 

[Airwolf75]

That's an almost larvae sea urchin.

 

[LeslieH]

Sorry, not an echinoderm. I suspect they're either newly settled colonial tunicates like Botryllus or Botrylloides or possibility a bryozoan. Here are images of some further along in their development:
http://convoluta.ucdavis.edu/gallery/view_album.php?set_albumName=Botrylloides
http://convoluta.ucdavis.edu/galler...icornis&id=Schizoporella_14May06_atmost4weeks

 

[ReeferAl]

Thanks Leslie. I think you've nailed it. Some of those photos look darn close to what I've got. It would appear they are harmless and I don't need to worry that my QT is infested.

Allen