ID this stuff please
 

This pink stuff is growing under this rock and on some other rocks too.

http://i134.photobucket.com/albums/q...2/IMG_3805.jpg

Thanks

Looks like sponge to me. And if it is, I hope that pic wasn't taken above water :)

I would agree. Looks like some nice sponge growth.

My guess is sponge, I have the same stuff growing on the bottom of my rocks also.

Pic was taken under water. Good to know it's nothing to worry about.

Thanks

Dose look like a sponge of some sort. Was it a hitchhicker?

the fact its growing on the underside and hes concerned to know what it is, makes me think he didn't buy it but thats my opinion.

Sponge------ I have them in red, orange, purple, green, black & white.
Good filters. There are far worse hitch hikers you can get.:wink:

Definitely true, Greg! But here's a question: has anyone had a sponge overgrow corals? Are they dangerous in that sense? And if so, how do you trim them back/keep them in check?

Sponges that encrust the rock IME generally grow in low light areas so they don't compete with the coral. Also the corals give off toxins to ward off intruding species. I have had sponges grow beside a coral but never compete for the same space. Some sponges have long thin stringy branches that don't look very nice so those I have just pulled off or cut with scissors.