Sponge? Macro? Please help me ID this stuff!

[Blinky]

Hi guys! I'm glad AC is back :)

I've got something growing all over the base of my fox coral. It's shaded, so I wondered if it might be some sort of sponge, but it looks to me like it could be a red macroalgae. It's growing quickly, none of the fish or crabs are interested in eating it. For size reference this is a small 1/2 cup container. Any thoughts?

http://i8.photobucket.com/albums/a21/ACBlinky/Misc/unknown.jpg

http://i8.photobucket.com/albums/a21/ACBlinky/Misc/unknown2.jpg

[Fishieness]

macro. not sure of an exact spcies though, sorry.

[mogurnda]

Definitely a red macroalga. Looks like Scinaia to me. Whenever I get a cool macro like that, something eats it.

[Blinky]

Wow, thanks Dave I think that's right on!

The tank has really started to settle, it's starting to look very 'lived in' and the paramters are much more stable with N & P always undetectable thanks to the Chaeto in the fuge. I'm seeing more life coming out of the rock and the bases of the corals, and I attribute that to good water quality - I know things like Valonia are undesirable to most people but I consider it a good sign, since it prefers a clean tank. I wonder if this red algae is the same; I've had the fox for ages, but only started seeing this algae take off in the past little while.

[Germanman]

for later instances sponges cant touch air because the osculum gets cloged and they rot from the inside out.

[Blinky]

Yep, I was aware that sponges and air don't mix - just in case, I lifted this guy out of the tank in the little cup and kept it in water.

[gkeren]

Your picture is great, very clear. When i first saw it it was driving me nuts, I had to break out a book of mine and find it, I had dried this specimen years ago, during a research trip.

You have a Rhodymenia pseudopalmata. Very beautiful specimen you have.
I found a site with some info for you....
http://www.horta.uac.pt/species/Algae/Rhodymenia_pseudopalmata/Rhodymenia_pseudopalmata.htm

[Blinky]

Thanks for that! I spent hours last night looking at pictures of seaweeds, made myself dizzy! Here's a pic of it growing in the tank, it's bizarre how it only comes from this one spot. This coral was in the LFS tank for a good six months before I bought it, and it's been in my tank for at least another four, and just recently this macro appeared.

http://i8.photobucket.com/albums/a21/ACBlinky/Misc/redmacroFeb2.jpg