<a href=showthread.php?s=&postid=11299259#post11299259 target=_blank>Originally posted</a> by MUCHO REEF
Sponge, if I'm seeing it clearly, it grows like crazy. You have to remove the rock, place it in a shallow bowl of tank water, just enough to submerge the frag/colony. Using a new tooth brush, gently brush between each polyp until you have removed it all. Use a second or third small bowl of tank water to finish off the job. Be very careful not to damage any polyps. It might not open for a day or so afterwards, this is common, just place in current until it does and it will be fine. I had to remove a 6 inch rock last summer to remove the same type of sponge which was covering the rock and migrating to another rock. If left unchecked, it will grow and migrate like crazy. Good luck.
Mucho Reef