Whats this??

[SWINGRRRR]

It seems like Coraline, but its real fuzzy. There are 2 patches of it on this same rock.

[catchndolphn]

sponge?

[KADLETZ]

sponge.

[SWINGRRRR]

good or bad?

[lobstergrabber]

I agree that it is a sponge as well. They filter feed and I would consider them good.

Rich

[JaredWaites]

<a href=showthread.php?s=&postid=11453218#post11453218 target=_blank>Originally posted</a> by lobstergrabber
I agree that it is a sponge as well. They filter feed and I would consider them good.

Rich

Well just because they are filter feeders doesn't mean they are a good sponge, keep that in mind.

Some encrusting sponges are a PITA and grow fast and will encrust over corals. Like certain Paly's will do as well.

Only time will tell unless you can get a good ID on it.

[60Cubed]

It should be fine. Most sponges are reef safe. I have never had a problem with them. I wouldn't worry about it.

[AnOldSalt]

A growing sponge is generally a safe sponge. Even the bad ones are mostly harmless unless they get chewed on or otherwise don't make it.

Do any of you have any motile sponges in your tanks? Yellow ball walking sponge is common enough, but I mean any of those flat oozy types which crawl around like a giant amoeba in your tank. Those are just the coolest little guys, if tricky to keep. That Calfo/Fenner inverts book has one on the front cover, as I recall. Very pretty.