White spots on my live rock

[Billan]

I have recently noticed some white spots that are very odd in shape on some of my rocks that are near the bottom of my tank. They are anywhere from an inch to two inches across and look like someone put white glue on the rocks. Any idea what this is?

 

[davelin315]

Most likely a sponge or tunicate of some sort. If you can, post a picture. One thing to look for is if it is either porous looking or if it has a "spout" at one end.