White Spots on Coralline (not spirobid)

[holy carp]

Has anyone seen spots like this?  They are forming primarily on the coralline algae in my tank, and I've been seeing them spring up over the last month or so.  They are very flat and in most cases a ring.  Not sure if these could be eggs of some sort, or some type of bite mark.  I'll try to get a better photo tonight.  Many areas of coralline are completely unaffected while others are densely speckled as below:

[dandelion]

I had some white spots too on mine but they don't have the little target like dot at the center. Just white bumps really. Looked like growth spots to me.

[RayWhisperer]

Are they separate from the algae, or somehow incorporated into its growth? I guess that seems like a dumb question. I'll try a better question.... Are they actually growing over the existing algae, or does it look more like a discolored part of the existing algae?

 

Also, growth form. Assuming it's separate from the algae. Is there a different growth pattern?

[holy carp]

So, as best I can tell, they seem to be a spot growing ON the algae, which may be killing/consuming the surrounding algae tissue and only leaving a white ring of the calcium that the coralline had deposited in the past.  As far as I can tell, these have not affected corals in any way.

 

I've managed to take a few more photos.  Tonight I'll try to get another photo of the same spot I had originally shot, so we can see the change over time.  These spots are more recently formed on the skeleton of my torch coral, which was closed last night:

same spot, different focus:

 

And here's on another section of live rock where I was able to get pretty good focus.  Again, these are small (that's a nano conch to the left and a tiny colonista snail next to it) and tough to focus with a smartphone.

[EDIT: I had increased feeding significantly over the last couple weeks to try to revive my sunset montipora.  As a result, my phosphates have been higher than normal recently (i.e. .12 yesterday vs normally ~.03).  I added phosguard last night]

[RayWhisperer]

Well, I done some reading and searching, I've come up empty as of yet. I read something once about lethal orange disease in coralline. So, it seemed plausible. I searched for that, it's not what you have. However, in doing so, I read about white band disease and white spot disease on coralline. I never knew this effected coralline. I thought it only attacked acros. I was wrong. Bad news, nothing is known about it, and I couldn't find any pics for comparison to what you have.

 

With that said, in the mean time. Why don't we cover some of the basics? I'm pretty sure you're ok, but here we go. How bout ca, alk, and mg numbers? Another one to get out of the way. Do you notice any asterina stars near the spots? Do you, by chance, have a significant number of said stars in your tank?

 

The search will continue. Just not right now.

[RayWhisperer]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4493676/#!po=10.6061

A little light reading on white band and white spot to pass your time.

[RayWhisperer]

I've been diggin on this for quite a while now. I can't find anything to match what you've go going on. It doesn't match white patch, or white band disease. For that matter it doesn't match anything I can find. My initial thoughts were foraminiferans, or perhaps some type of radiolan. Without any further description, I can't see it being forams. It turns out there are no benthic forms of radiolan, so that went right out the window, too. Besides, I can't find any documentation of forams killing surrounding coralline, nor can I see a reason why, or how they would. I'm stumped if it's not something common like asterina.

[holy carp]

Sorry, I haven't been on in a few days, but I appreciate your research.

 

I'll try to do a full parameter test tonight, but since I've been noticing these spots, my parameters have been in these ranges:

Alk 7-8

Ca 325-350

Mg 1250-1350

Sg 1.025-1.026

 

I have some asterinia starfish in the sump, I've never seen them in the display.  I have lots of the white (not banded) micro brittle stars in the sandbed and in nooks on the rocks.  They have been a significant population for a long time before this started to be visible on the coralline.

 

I only skimmed the white band white spot article, and while those don't sound the same as what I see on my coralline, your comment about those diseases affecting acropora made me think... I have had tissue loss on some of my acros on the undersides where they are shaded that has been getting worse around the same time frame as these spots.  There don't seem to be evident spots or bite marks on the tissue.  Just tissue recession.  The tissue issues with the acros began in late January, and while I didn't notice these spots at that time, I did find them in some photos from around the last week of Jan that showed the spots starting.

 

So...  I went back through my notes, and on Jan 15, I had introduced 3 ceriths, 1 large nassarius, and 2 banded trochus.  Perhaps something was on the snail shells?

 

[RayWhisperer]

Dunno. I can't really see snails bringing something like that in. But really, what do any of us know? Most research on marine ecology/biology is pretty infantile. Add another factor of all of us just being hobbyists. We're down right dumb, when you get right down to it.

 

as far as params. Mag is low. That may be the factor, there. As coralline is a major mag consumer. However, I wouldn't think it the cause. More likely just a stressor.

 

i don't know if the same pathogens that cause white band in acros is the same as those in coralline. I got glassy eyed by about the 4th page on the article I linked.

 

We'll figure this our, one way or another.

[holy carp]

I took a few more photos, and have included prior photos of that spot for comparison...

 

Here's the initial from a week or so ago:

 

And here's the same spot yesterday evening:

 

Here was the skeleton of the torch coral last Thursday:

 

And here it was last night (5 days later):

 

At first I assumed these things were immotile, but that string of progressively larger white spots appears to be a trail which may support the foraminiferans idea.  Then again, WTF do I know?

[RayWhisperer]

Forms was the reason I asked about growth form/pattern early on. Many types of forms have a very recognizable growth pattern.

[Weetabix7]

This is so bizarre. 

Following along to see what happens....

[holy carp]

18 minutes ago, RayWhisperer said:

Forms was the reason I asked about growth form/pattern early on. Many types of forms have a very recognizable growth pattern.

 

Does this help, or is there something specific I should try to inspect?  Sorry, I guess I didn't quite understand what you meant by growth forms. 

 

I wonder if I can scrape some off...  If only I had a microscope.  Anyone in NYC with a microscope want to take a look at these?

 

Also, I just noticed that it seems a tiny one at the bottom, below the obvious trail of circles on the 2 torch coral photos has 'walked' around a bit as well.  However, I haven't noticed any of them being significantly off-center in their white circle as they were moving, so they must stay there in one spot for some time and then move more quickly to a new spot.  And they are either swimming, spawning into the water, or hitchhiking on snails/crabs, because they have appeared on all rocks and sections of the tank.

[teenyreef]

33 minutes ago, Weetabix7 said:

This is so bizarre. 

Following along to see what happens....

Me too! I have no idea what they are, though.

[RayWhisperer]

9 hours ago, holy carp said:

 

Does this help, or is there something specific I should try to inspect?  Sorry, I guess I didn't quite understand what you meant by growth forms. 

 

I wonder if I can scrape some off...  If only I had a microscope.  Anyone in NYC with a microscope want to take a look at these?

 

Also, I just noticed that it seems a tiny one at the bottom, below the obvious trail of circles on the 2 torch coral photos has 'walked' around a bit as well.  However, I haven't noticed any of them being significantly off-center in their white circle as they were moving, so they must stay there in one spot for some time and then move more quickly to a new spot.  And they are either swimming, spawning into the water, or hitchhiking on snails/crabs, because they have appeared on all rocks and sections of the tank.

if you read that thread, Evil mentions a spiral form, similar to a snail. That was a solid clue that it was most likely foraminiferans. That's by no means the only growth form they have. Some are arrow shaped, some look like funky diamond shaped, loads of variations, even the hard red branch things that come in on live rock are a type of foraminiferan. It's thought they are one of the most common life forms in the ocean, yet most hobbiests wouldn't even know what one is. This would go a long way to explaining why they are everywhere in your tank.

 

im pretty sold on the foraminiferan theory, I just want to be "more" sold.

[holy carp]

OK, so these things continue to progress, so I have a bit of a photo-dump to catch up here:

First, looking at the torch, the spots continue to move and reproduce, but not as aggressively as in other spots. However, I've yet to see any that have grown in size larger than these.

In other areas, the coralline has gotten more thoroughly consumed

I was finally able to get some under a microscope.
Some look like aliens! 

 

@RayWhisperer I think you might be onto something with the foraminiferans guess...

[kimberbee]

They look like gross nipples... I hope no one was looking over my shoulder cause I'm at work! 

[RayWhisperer]

Wow. I just don't know what else to say....

 

Look at the spiral growth that you can make out in the last 3 pics. I'm about 99% sold on foraminiferans. I think the only way you'll get a more definitive ID is through Fenner, or some other over at WWM. Cool pics.

[RayWhisperer]

I was doing some reading on limpets, and found something of interest. 

Puncturella aethiopica a species related to the keyhole limpet,  that has been observed to feed on Foraminafera. 

I can't find much of anything on them. I did find they are found in African waters. So, not much luck in getting some collected for you. However, maybe some other members of the genus, more local to us, feed on them....  

[wysoczak]

/Hello reefers, 

 

I wanted to see if you by chance have found out what this was, as I have found these white dots in my tank and cannot figure out what they are, i just tested my parameters and found that the Alk is a little low but other than the rest of my parameters are normal. Please help, hopefully someone still watches this thread. 

[holy carp]

I was never able to get a positive identification.  Forams was the leading contender. 

 

Now 2 years later, they still live in my tank and have never seen a specimen grow larger than the 1-2mm diameter size. 

[mndfreeze]

The white spots could be its chemical defense/offense against other immobile space hogs like plants and coral.  Could be some weird type of sponge or some other microlife and it's not eating the corraline as much as just making space for itself.  Lots of plants and animals do it.

[holy carp]

Interesting hypothesis.  I'd say it is possible, but I think it is unlikely since the spots do not stay there after the coralline has been consumed.  I would assume if they were trying to stake a territorial claim but did not need the coralline as food they would probably just stay there after the coralline died.

 

The 2nd picture compared to the first on the March 15, 2017 post seems to show they don't remain in the areas where the coralline has been cleared.  On the other hand, perhaps they kill their substrate and then flake off to their peril.