What is going on with my coralline?

For the last several weeks, there's been a trail of missing coralline in a circle on one rock. I figured I must have scratched it off when moving it around, and that it would grow back. Upon closer examination, it's like something has eaten it away, and I've been picking off asterina stars from it from time to time. However, the asterina stars leave splotchy patches, while this section looks like it's been mowed through.

This morning when the lights came on, I was surprised to see that a yellow trail has developed through the same circles overnight; it was not there yesterday. I don't see animals (did pick off one small asterina, but he was nowhere near it) and that spongy thing near the top I believe was poop (picked it off as well).

Anyone have any ideas? It's literally yellow.

 

Someone else on this site had the same problem. I'm hoping they will chime in. Apparently it's some sort of a bacterial disease?

 

Asternia stars?

Opps I should really read the entire post. I do believe it was the asternia star. I have read several other post about coralline turning orange after finding those stars in the tank.

Biff is right There is some sort of bacteria that does eat the coralline as well. Cant find that post.

Okay I found it, you are not going to like it, its called Coraline leathal orange disease or CLOD you should Goggle it

 

I haven't seen enough conclusive evidence to say asterina stars do that.I've got plenty of coraline, I've got plenty of asterina stars....but I've never seen that in my tank. I think the majority of tanks have asterina stars in them, but we only get this question every once in awhile.

I think they're getting a bad reputation for doing something that they're not responsible for.

But I could be wrong, I would love to see one of the asterina stars in action actually making those marks.

 

I also have a gazillion asterina stars, and have never had orange/yellow coralline in my tank. That's why I initially thought of the bacterial disease.

 

I found this on the subject:

Lethal Orange Disease (LOD): A yet unknown bacterial pathogen causes death of the reef-building coralline algae Porolithon onkodes. This coralline alga is the principle cementing agent that maintains the intertidal wave-resistant reef crest. It helps the coral reef community by cementing together sand, coral fragments, and other debris into a suitable hard substrate for the establishment of coral colonies. It absorbs wave energy in the outer reef rim that would otherwise erode the shoreline and destroy many shallow-water reef communities. LOD leaves the coralline algae skeleton white as it progresses in an orange band, destroying the algae (fig.22). When spreading, the front reaches the margin of the algal thallus, it forms upright filaments and globules, similar to those formed by terrestrial slime molds. The globules can be caught by waves and easily spread to nearby corallines.

 

+1 PRC
Asterina stars get a bad rap for so many things.

 

That one snail in the picture was there all day and all night, doing circles on it. I think he's trying to eat it, or he's snail indiana jones trying to solve the markings...

I'll keep an eye on it. :zombie:

 

Seems crazy to me...I have no idea. Let us know of further developments, Im curious.

 

It started to fade last night, and this evening it's all but gone. It's still there, but so faded it's hard to see. That snail is still making circles. Have no clue.

 

Take another picture of it faded so we have it for future reference.

 

Do you see the smoothest purple coralline "shedding" at all, sometimes little flake dust like films will start coming off where it is receding. A lot of the titanoderma species do that, and I think the purple coralline that is effected is a Titanoderma species, something like Titanoderma protyotypum.

Has the yellow stayed? Maybe it is a different epiphyte species of coralline. You have more than 4 different species of coralline on that rock already it looks like.