Cotton wool eggs? (Red Sea)

It looks like 2-10cm lumps of cotton wool hanging on corals, ropes and debris. There were a lot of this things at this dive site in northern Red Sea. It might by someones eggs. What is this?

I'd be interested to know this, I have photos of these from Bunaken, only small ones tho, no more than an inch in diameter, a cluster of about 10

I'm having a guess at cuttlefish eggs?

Being "cotton" it's more likely to be tufts of cyanobacteria. They come in a variety of colors although red is very common.

I've googled both cuttlefish eggs and cyanobacteria tufts. Cuttlefish eggs looks entierly different - they have round symmetry and looks like slightly deflated toy balloons. Cyanobacteria tufts looks more closer, but in most photos they covers bottom like moss and I haven't found any photos with the same color.

I'm no expert at all! I think Leslie is tho!!!

The ones I saw in Bunaken were circular unlike yours, same red/purple colour in a cluster of about 10 so was thinking of mine rather than yours

Color varies. So does shape as that can depend on whether it's on the seafloor or covering a rock or waving in the current. Also, the shape changes when the cyanobacteria produce air bubbles that lift up the algae. On the other hand, you saw it for real and I'm just guessing. :-)

I videoed this on a night dive at Koh Ta Chai, north of Thailand's Similan Islands. It appears to be sticking to a worm and the moment I have it scientifically classified as "candy floss worm" lol. You think this is cyanobacteria, Leslie?

Color varies. So does shape as that can depend on whether it's on the seafloor or covering a rock or waving in the current. Also, the shape changes when the cyanobacteria produce air bubbles that lift up the algae. On the other hand, you saw it for real and I'm just guessing. :-)

There were little air bubbles inside this thing (link to full-sized image). I agree, most likely it's cyanobacteria. Thank you Leslie!

I videoed this on a night dive at Koh Ta Chai

It looks like pretty much the same as my thing. The only difference it's attached to the worm, while my things were attached to anything - corals, ropes, etc.

Glad I could point you in the right direction, BlackSir. :-))

Candy floss? Is that what yanks would call cotton candy, Nick? I do think that it is cyanobacteria attached to the calcareous operculum of a christmas tree worm. They often get overgrown by algae & such.

Candy floss? Is that what yanks would call cotton candy, Nick?

Yeah, we wanted our own word for it, even though you lot invented the stuff. Gotta laugh at the irony of the candy floss inventor being a DENTIST

Thanks for the ID

maybe these are different to those?

Can anyone help in clarifying these please?

Something different. That's the red algae Gibsmithia. There are 4 species according to algaebase and it seems closest to G. hawaiiensis

http://www.algaebase.org/search/species/de...species_id=4334

http://university.uog.edu/botany/474/rhodo...thia.html#dotyi

Awesome Leslie, thank you so much