Does this look like pissible PMD?

[Tonycass12]

Just looking for some help here. I have 2 maxima clams in my tank. 120gal sps dominant, lit by reefbreeders and radions. Clams sit ontop of the rock structure and get 500+par. One of the clams I've had for nearly 2 years the other for about a year. They are both 7-8". Over the last few months I've noticed my older clams growth has slowed and some of the folds in the mantel seamed to be tucked in more often then not. My newer clam looks much better but one end of the mantel has started to pull in a majority of the time. The newer clam still has a very bright white new section of shell and has actually nearly caught up to the older clam that used to be at least a couple inches longer. You can see some aptasia near the mantel on my older clam. I occasionally scrape it away or inect in with some kalk paste but they seam to always come back. I'm slowly winning the aptasia fight in my system but it's nowhere near over.

Salinity 1.026
Alk 7.5
P0⁴ .5 -my system has run high P04 for the last year since I moved into a larger tank.
N0³ 28.3
Ca 390
Mg 1270
I'm hesitant to give these clams an ro dip without being more positive about a PMD diagnosis.

Here are some photos of the larger older maxima thismorning.

Here is my newer slightly smaller maxima. This one is in better shape with continued growth. You can see the right end of the mantel is pulled in.

Older pic when my bigger clam was in better shape.

And one of the newer smaller clam shortly after I got it.

I'm interested to see what you guys think about this.

 

[Tonycass12]

@OrionN

 

[Tcook]

Those clams are not “new”. I would think pmd is infectious process brought in by new clams, maybe more so wild cought. Have uou checked for pyramid snails? The aptasia doesn’t help. Ca and mag a bit low. I also don’t see much new shell growth. Need another clam expert @minus9

 

[Tonycass12]

Those clams are not “new”. I would think pmd is infectious process brought in by new clams, maybe more so wild cought. Have uou checked for pyramid snails? The aptasia doesn’t help. Ca and mag a bit low. I also don’t see much new shell growth. Need another clam expert @minus9

I was very aggressive with cleaning when they were brought in. No pyramid snails. I've checked multiple times since ive gotten them and never seen any. I know the aptasia could be an irritating factor but I see areas of the mantle pulled in that don't touch anything. I wasn't aware that PMD is something you only get with newer clams or systems that have new clams being introduced? The older clam has had growth pretty much stop. It's only got a very thin white band under the mantle. The newer clam still has 1/4" of crisp white shell its forming but its mantle still hangs far enough out to cover it all, you can only see it when the mantle pulls in.

Hopefully I'm not being confusing referring to the clam as the old or newer one.

Calcium alk and mag are all lower then I typically like. My sps are going through a serious growth spurt at the moment and I've been upping my dose every week. I'm doing another round of testing this afternoon and I'll post the results here. The ones I posted earlier were from last week.

 

[minus9]

Are the older clams wild caught? The first one looks to be wild? I also don’t see any new growth on its shell. Same with a few others, no noticeable growth. I see possible irritation from aiptasia. With PMD, you’ll find that the mantle will have a “crinkle” appearance at first, then it moves up the mantle. Also, you would have to introduce the pathogen from another clam or infected system for it to be PMD.
The one thing I notice with wild caught maximas (usually) they’ll be okay for a while and appear to have some growth, only to stop at some point and slowly wither away. The length of time where they seem okay varies, but the end result is usually the same.
Any fish going after the mantle? CBB and tangs can and will nip at mantles. If coral growth is good, then I don’t think you have a carbon limitation issue, which I find with older systems with high PO4.

 

[Tonycass12]

Are the older clams wild caught? The first one looks to be wild? I also don’t see any new growth on its shell. Same with a few others, no noticeable growth. I see possible irritation from aiptasia. With PMD, you’ll find that the mantle will have a “crinkle” appearance at first, then it moves up the mantle. Also, you would have to introduce the pathogen from another clam or infected system for it to be PMD.
The one thing I notice with wild caught maximas (usually) they’ll be okay for a while and appear to have some growth, only to stop at some point and slowly wither away. The length of time where they seem okay varies, but the end result is usually the same.
Any fish going after the mantle? CBB and tangs can and will nip at mantles. If coral growth is good, then I don’t think you have a carbon limitation issue, which I find with older systems with high PO4.

I dont see any of the fish ever picking at the mantel. The tangs pick algae off the shells but that's all. The older of the two may be wild im not really sure it has a interesting oyster looking mollusk attached to its shell so that may point to it being a wild harvested clam.


This is leaving me scratching my head as to what the issue could be.
Updates parameters
Salinity 1.026
Alk 7.1 just upped the dose again
P0⁴ .51
N0³ 25.9
Ca 405
Mg 1265 gave this a big one time dose so I should see a decent increase in my next round of tests.

 

[Tonycass12]

You can see the new shell growth on my smaller/newer clam

Not the case with the older/larger clam.

 

[minus9]

A couple things you can try (slowly increasing mag will help), increasing light intensity a little, increase feeding fish (smaller meals throughout the day) and carbon dosing (not with Nopox). Based on your PO4 level, I would recommend using Tropic Marin Elimi-NP (start at half the recommended amount) then increased by 0.1mL per week.

 

[Tonycass12]

A couple things you can try (slowly increasing mag will help), increasing light intensity a little, increase feeding fish (smaller meals throughout the day) and carbon dosing (not with Nopox). Based on your PO4 level, I would recommend using Tropic Marin Elimi-NP (start at half the recommended amount) then increased by 0.1mL per week.

I've been slowly trying to bring P0⁴ down its been high for a year now, and long before the clams were having any issues. I cant bring my lights up anymore because I was torching my sps. I had lowered the light intensity a little because I was getting readings of 400par on the sand. The top of my rocks was around 750par and it caused some of my sps to pale out. Currently the clams sit in spots that are over 500par. I would think thats more then enough intensity no? I'm going to start with just trying to get magnesium back up to where it should be and see if anything changes with just that first. I don't like trying multiple things at once because then if something goes wrong it's too hard to pinpoint what it was. Thanks for the tips!

 

[minus9]

I've been slowly trying to bring P0⁴ down its been high for a year now, and long before the clams were having any issues. I cant bring my lights up anymore because I was torching my sps. I had lowered the light intensity a little because I was getting readings of 400par on the sand. The top of my rocks was around 750par and it caused some of my sps to pale out. Currently the clams sit in spots that are over 500par. I would think thats more then enough intensity no? I'm going to start with just trying to get magnesium back up to where it should be and see if anything changes with just that first. I don't like trying multiple things at once because then if something goes wrong it's too hard to pinpoint what it was. Thanks for the tips!

Yeah, that seems like plenty of light to me, but each clam is different and will require different light intensities. I'm the same, change one thing at a time and see what happens. The other thing I like for "feeding" the tank and also has the benefit of reducing nutrients is PNS Probio. I've always noticed improvements when dosing it.

 

[Tonycass12]

Well moving a couple things around and went to adjust how my troubled maxima is sitting. It's foot is gone. It had been attached to a 3x3 frag tile since shortly after I got it. Something must have happened and the foot got damaged and dropped. The base of the clam where the foot should be seams to actually be concave back into the clam flesh with a white muscle looking tissue up both sides of the shell around the opening.

I'm thinking this damage is why it hasent been extending its mantel as much. And the growth has stopped. I'm feeling like it may just be a slow downhill for this clam unless it grows another foot and re attaches.

 

[minus9]

Can you take a pic of the bottom of the clam in daylight? They have the ability to drop the byssal threads “bundle”, which will regrow, but if the actual byssal organ was damaged, that’s a different story.

 

[Tonycass12]

Can you take a pic of the bottom of the clam in daylight? They have the ability to drop the byssal threads “bundle”, which will regrow, but if the actual byssal organ was damaged, that’s a different story.

The thread looking filament in the photo is a ripped apart aptasia from picking it up off the rock. I think the byssal organ is damaged. You can see the muscle like white flesh along the right side in the photo. It has it on the left too. Im most concerened that it just looks like open flesh in the center.

 

[minus9]

That looks a little concerning. The tissue should cover the byssal opening fully. Give it a day to see if the organ fills out the opening and looks normal again. You shouldn’t be able to see inside the clam through the byssal opening.

 

[Tonycass12]

That looks a little concerning. The tissue should cover the byssal opening fully. Give it a day to see if the organ fills out the opening and looks normal again. You shouldn’t be able to see inside the clam through the byssal opening.

Yeah, it's been like this for at least a week now. I've got it sitting where it can re attach to the rock, but I don't have super high hopes with how this might turn out. I'll keep it where it's at from here on out and try not to mess with it. I'll post here with updates if I have any changes.

 

[minus9]

Is there any new growth on the shell?

 

[Tonycass12]

Very very thin line of white shell but it's rate of growth is just enough to be noticeable. Much slower then its ever been. My other maxima is quickly catching up to it size wise.

Is there any new growth on the shell?

 

[minus9]

Very very thin line of white shell but it's rate of growth is just enough to be noticeable. Much slower then its ever been. My other maxima is quickly catching up to it size wise.

That’s good to hear. There’s always hope when you see some growth.

 

[ArachnoJoozt]

The thread looking filament in the photo is a ripped apart aptasia from picking it up off the rock. I think the byssal organ is damaged. You can see the muscle like white flesh along the right side in the photo. It has it on the left too. Im most concerened that it just looks like open flesh in the center.

Could this aiptaisia which was practically on the foot have irritated the clam to the point of breaking its byssal threads to look for a better place? (and not finding it because the aiptaisia hitchhiked along?)

 

[minus9]

Clams can drop their bundle of threads without issue. They’ll simply use new byssal threads to reattach, which may be what happened here?