After more research, I think that it is not Haliclona sp. but more like Leucosolenia sp.
http://www.biosci.ohiou.edu/introbio...ucosolenia.htm
http://images.google.com/images?hl=e...ia&btnG=Search
Bob_I,
AJ_77,
monza,
dirtyreefer &
teevee; Thanks for the feedback. It has given me some ideas about how I want to proceed from here.
The photo I uploaded was from my feature rock which is 22" x 10" x 10" weighing approximately 40 lbs. That is going to be in my main display, so the sponge has got to go.
Some of the smaller rocks with sponges may end up in my sump, maybe the biodiversity will be beneficial. I can deal with it there.
Thanks again. I'll let you know how my experiment works out.