Help with Tridacna maxima clam

[skyfreak73]

Hello reefers,

Looking for T. maxima specialists for some advice. About 2 weeks ago I brought home a beautiful show piece, but about a week ago it started exhibiting some retracted mantle. I think it may have pinched mantle syndrome, and I'm considering a freshwater dip. I have two T. crocea and one T. derasa doing fine, but I did lose a smaller T. maxima about a week prior to adding this one. I waited too long to do a FW dip on the last one...it looked like it was bouncing back 24 hours after the dip but then started to get progressively worse about 48 hours after the dip.

So my dilemma is to dip or not to dip. I had told myself that if I saw signs of it getting progressively worse, I would dip. Today there is more of the mantle retracted than there was a couple of days ago when I took the first picture.

TIA!

/sf

 

[kevindub]

That's a nice and big clam. Freshwater dips will only help if it is parasites that are attacking it. It is worth a shot. But there are other things that attack clams like bacteria and protozoa that are hard to fix. I have heard bacteria wiping out a lot of clams. Maybe there is something that only attacks maxima clams in your tank. I think the only thing you can do is a fw dip and maybe try a new spot for the clam. Water changes never hurt too.

 

[skyfreak73]

Thanks for the advice, kevindub. Since I lost another, small maxima I'm wondering if my water column has some kind of pathogen. I have a UV sterilizer but hesitate to use it since I'm using the Polyp Lab System Reef-resh. Perhaps I stop dosing with the the Polyp Lab and run the UV sterilizer for a 4-5 day cycle.

Thoughts?

/sf

 

[chris&barb]

Thats not pinched mantle. Pinched mantle has very distinct symptoms and your clam is showing non of them.

You have a fish nipping at the clam. The blennie in the first photo is a clam nipper but it may be another fish thats doing it. Can you list all fish you have?

For now cut the top off of a clear 2L soda bottle and drill a bunch of small holes in it for water flow and place this over the clam to protect it.

 

[Anonymous]

Hey Mike, Craig from AquaTek here. First off:
:welcome:

Chris and Barb had a great suggestion there; sorry that we didn't think of that in the shop on Monday.
Maybe they can weigh in again and provide a description of the symptoms that do indicate pinched mantle... for future reference.

How's the clam looking today?

 

[chris&barb]

Typically you will see an upward and inward curling of the mantle and many times there will also be slim coming from where the shell and mantle meet.

By chris_barb at 2007-05-13

 

[chris&barb]

Heres a different clam from a different angle

By chris_barb at 2007-05-13

 

[skyfreak73]

Hey Mike, Craig from AquaTek here. First off:
:welcome:

Chris and Barb had a great suggestion there; sorry that we didn't think of that in the shop on Monday.
Maybe they can weigh in again and provide a description of the symptoms that do indicate pinched mantle... for future reference.

How's the clam looking today?

Thanks, Craig!

Clam looks the same as it did yesterday.

You have a fish nipping at the clam. The blennie in the first photo is a clam nipper but it may be another fish thats doing it. Can you list all fish you have?

After the suggestion, I think it is perhaps my Kole tang that may be nipping the mantle inadvertently as he grazes off the sides of the shell. I've seen him a couple of times today graze the shell right at the edge of the mantle and the clam reflexively pulled back for a bit. I haven't seen the Midas blenny pay any attention to it.

Here's the full list of fishes:

Blue Assessor
Cryptic Wrasse
Mandarin Dragonet
Flame Hawkfish
Midas Blenny
Kole Tang

For now cut the top off of a clear 2L soda bottle and drill a bunch of small holes in it for water flow and place this over the clam to protect it.

The clam is a bit too large to fit under a 2L soda bottle (or even a 3L). I may try to devise another method...perhaps some mesh or netting. But I feel better about the pinched mantle and not doing a FW dip. The T. maxima I lost previously did exhibit the symptoms described with significant curling in of the mantle.

Thanks for all the suggestions folks.

 

[Minh Nguyen]

It does not look like PMD to me either. For a large clam like that PMD take a long time to kill (Months). Some thing is bothering your clam. Keep an eye on it. Large Maxima tolerate FWD very well, but I don't think it would help at this time. Good luck.

 

[skyfreak73]

First of all, thanks to everyone for the helpful information. I'm afraid that things have not improved, though I'm still up in the air as to the cause and how to help this clam recover. I've attached the most recent (15 minutes ago) pics for your review. The mantle is now completely receded, and in the corners it looks like it may be folded in and possibly even detaching from the shell.

I would appreciate any advice. My LFS has offered to quarantine him for me in case other tank inhabitants are bothering the clam (again, my suspect is the Kole tang and/or my reef janitors), but I don't want to further any stress on the clam if anyone has any other suggestions.

TIA!

 

[Anonymous]

Ouch, Mike, that doesn't look good at all. Let's hope Chris or Minh checks in tomorrow morning so we can get some more expert advice.

There's a spot already cleared for you in the front of the reef tank, so if that's what you decide to do, just bring it on in.

Fingers Crossed,

Craig

 

[Minh Nguyen]

I am not sure what it is that is killing the clam. I have seen advance PMD look like that.
This clam will die if you don't do anything, it is getting worst and doing nothing it will die. Because of this I would FWD it in hope that it may be PMD. At this point you really have nothing to loose. Good luck.

 

[chris&barb]

have you tried to cover the clam at all? find something clear that will cover the clam, allow flow and keep all fish away from it and cover it.

 

[skyfreak73]

have you tried to cover the clam at all? find something clear that will cover the clam, allow flow and keep all fish away from it and cover it.

I haven't been able to find something adequate to cover it. Perhaps a 1G water bottle would work. I'll do that immediately.

Ouch, Mike, that doesn't look good at all. Let's hope Chris or Minh checks in tomorrow morning so we can get some more expert advice.

There's a spot already cleared for you in the front of the reef tank, so if that's what you decide to do, just bring it on in.

Thanks. I'm worried now that if I bring it in and it does have some kind of infection, that it could spread to the other clams you have in the tank, and I'd hate to see that.

 

[jamesw]

Hi Sky,

In the past when I had a fish pestering a clam, I used a plastic cage over the clam and that helped. A good plastic cage for this clam would be a strawberry/raspberry/blueberry container from the grocery store. Just put the clam on the sand, put the cage over the clam and weight it w/ a few rocks or pieces of ceramic tile.

Cheers
James

 

[skyfreak73]

Thanks, but this clam is too large to fit into a container like that. I just put the clam into a container with some salt water that I've had mixed and at temperature for the last couple of weeks as a final resort, but my clam looks like it's on its last leg today. I don't think it will survive the day...


This is discouraging enough to make me want to stop reef keeping completely...

 

[skyfreak73]

Well, I think she's almost dead...will be by sundown.

After losing two T. maxima clams (including this one), and now with a T. crocea showing symptoms of PMD as described above, I feel convinced that I have a systemic issue.

Though you can't tell from the picture, the T. crocea has some filaments coming out from where the mantle meets the shell. I presume that's the slime that chris&barb mentioned as one of the symptoms.

 

[Anonymous]

My bi color blenny picked at my maxima and crocea. Instead of tearing down my tank to get the blenny, I sold the clams. It could be your Midas blenny. My blenny picked on the maxima more than the crocea. The fish is cool but I would rather have the clams back.

 

[skyfreak73]

My bi color blenny picked at my maxima and crocea. Instead of tearing down my tank to get the blenny, I sold the clams. It could be your Midas blenny. My blenny picked on the maxima more than the crocea. The fish is cool but I would rather have the clams back.

Thanks for the suggestion. I watch my tank obsessively, and I haven't seen the Midas blenny pay any attention at all to any of my clams. Given the symptoms of PMD I'm seeing on one of my T. crocea clams though, I don't think it's a fish that harassed it to death.

 

[skyfreak73]

So now that I've lost two maximas and it looks like I have a crocea affected with PMD, it begs the question: can/does PMD spread to other clams in the tank? If so, how do you eliminate those pathogens from the water column? If the crocea responds to a FW dip, but a pathogen is still alive in my water column, will the FW dip prevent reinfection? I've got another crocea in the tank that does not seem affected at the moment as well as a derasa.

That is...if I decide to keep my tank running. I'm still teetering on the edge of selling what livestock I can, tearing down my tank, and walking away from this hobby cutting my losses. Reef keeping is supposed to be rewarding...

**SIGH**