What is this on my rock?

Ever since I put my LR in the tank it has had this white/pink layer on it. It never seemed to do any harm so I did not bother with it, but in the last week it seems to have come alive like the Blob. It has started growing tendrils and reaching out. So I think I need to identify it! Does anyone have this and what is it?

Thanks, Mike

Edit Oops forgot the picture

 

It looks like some sort of a sponge to me, I'll see what I can find out for you. John

 

Perhaps Clathrina sp. ??

 

SPONGE! Over the last few months that stuff has been growing all over my tank...pretty cool...but i might have to start trimming it, its starting to grow into huge colonies! Always love the freebies

 

It's amazing how you will ignore or say 'that looks nice' when it just lays there, but when it starts spreading it becomes a threat until you know what it is! Thanks for the help guys. One of these days I will figure out how to ID these things myself.

Mike

 

I agree its a sponge, it has holes like a ball sponge. I have some growing in my tank. Look at the hole you will see it growing upward they look like little funnels and it thin. That's how sponges grow in thickness.

 

I'd have to say sponge as well. Those tentacles are probably feeders. coral_reefer says they will clean your tank. ;D

 

its a pink sponge i had it for a while then it kind of dwindled mine got real long also. maby yours will stay around or dwindle away like mine but when mine started going away i started getting yellow ball sponges not sure if it was a growth phase or just different type of sponge taking over

 

white sponge

It's some type of white sponge, I got some on a piece of live rock when i bought some soft coral. It tends to spread like crazy in your tank!!!! If you can pick it off, do it as soon as possible. Do not scrub it off with a toothbrush, because the small pieces that fall off spread throughout the tank; trust me on that

 

Fletch Nice ID, you are correct, maybe a Clathrina sp.. They can grow in a more flatish like overgrowth covering or in a branching mode. That whole white mass is the same sponge. Here are two examples




Those tentacles are probably feeders

Rick almost the whole body of a sponge is a feeder. Those large holes you see are osculums, the water excurrect hole. The branchs are just an extension.

It should have added it can als be a Leuconia sp so there is no 100% certainty