Sponge Question

[Samw]

If it is turning white, chances are that it has died. I'm no expert on sponges but I have had 2 blue ones. The first one turned completely white in less than a month (I threw it out) and the 2nd one is shrinking (but not turning white) and is still alive (after several months). I found out that they can kill acro millepora as the part of my millepora that was touching the blue sponge has died.

Hopefully, you didn't expose it to air as I heard that this would kill the sponge as well.