Mantle pinching (clam disease)

[Reefer Addict]

Well, this is more of an informative thread rather than a plea for help since I've already overcome the problem. I just figured I'd post this so if others come across this 'disease' in their tank they'll know what to do before any losses occur.

Anyway, I recently acquired two awesome maxima clams from clamsdirect, and after a couple of days of looking fantastic in my tank, their mantles stopped extending fully and looked all ruffled and pinched up. It started at one end of the clam and slowly progressed through all stages of the mantle.

Thinking it was a lighting or water quality issue, I moved the clams around and added some carbon to the tank to no avail... the clams still wouldn't extend.

In desperation, I searched the 'other' forum's clam section and found the treatment for the problem.

It's theorized that this 'disease' is caused by microscopic parasites that irritate the clam's mantle (though this is an educated guess), and it's 'cured' by dipping the clams in fresh RO or RO/DI water for 1/2 hour that has been equalized to the tank temperature. You can also equalize the pH to 8.3 if you're really paranoid about it... I didn't but the clams are looking 100% better today after treatment yesterday afternoon.

Please don't think I got these clams from Barry with the disease... chances are they caught it from my squamosa that I had previously. I bought the squamosa from another online vendor of which I cannot be sure if it were wild-caught. There's also still many unknowns about this disease, but at least there's a cure that has been working.

The disease also is suspected of only being able to infect proximate clams... meaning that clams immediately surrounding an infected clam are more prone to coming down with the parasite themselves rather than those across the tank.

The clams were also able to be placed right back into the reef rather than a quarentine tank, though all clams in your reef should be dipped at the same time so that you are sure none are a host that will reinfect the others.

So far things are looking good on my end, though I'm still keeping my fingers crossed. The clams look the best they have in a week.

I wish I had taken pictures of the clams when they were curled up, but my camera doesn't take the greates pix and they wouldn't be very informative. If you search the other forum for 'pinched mantle' you should come up with a thread that has pix and a lot of references.

Hope that helps somebody... I had planned on just 'riding this one out' but finally got worried enough to do a search... I'm glad I did because lack of treatment ususally ends in death for the clam.

[Geoff]

Thanks!!!

great information.

G~

[Barry N.]

WOW, Am sorry that this happened to your clam. Now and then, I get that as well and have dip them. With the thousands of clams that I have had in and shipped , only 3 times have I had to do this. Don't really think is a so called disease but more of a paritsite problem. I use baking soda to bring the pH up and leave them in there for 15 to 20 minutes. You clams HAS to be fairly healthy or it will not make it through the FWD.

[Reefer Addict]

No problem Geoff.

Barry,
you did your part and the clams arrived in great condition... now it's up to me to keep them that way. At no time did I suspect it was something on your end that caused it.
My clams had only shown symptoms for less than a week, which is why I think they have been doing well through the whole process.
They stayed closed up during the dip, and gaped for a while yesterday evening until lights out. I woke up this morning expecting to see them partially recovered, and to my amazement the 1.5" maxima's mantle was fully flattened (though not completely extended), and the 3" maxima had all but 1 section of its mantle fully extended.
It was quite a relief to know I wasn't going to lose my two new babies.
The wife and I are still checking your site daily waiting for the next round of 'jewels' to come up... I guess you can say we got the 'clam jones'.

I'll add a bit to my first post. The clams usually take 24-48 hours to fully recover from the dip, though some people have noted their clams took up to 3 or 4 days. You should wait at least 48 hours between freshwater dips if the clam isn't showing signs of recovery.
It isn't necessary to dip every clam in your tank like I stated originally, but at least dip those in close proximity to any infected clams.
If the parasite comes back, then you may wish to dip every clam.
The person who discovered the 'cure' to this problem, Minh Nguyen, lost 10 out of 17 clams before discovering a freshwater dip can help... that's gotta hurt.
On a final note, it's still up in the air as to whether this problem is transmitted clam-to-clam, or if in fact it is an opportunistic parasite brought into the reef from another organism.
The way the parasite kills the host is by preventing mantle extension and starving the clam. The clams can often suffer up to several months before succumbing to this parasite, but the longer they have been infected, the less likely they'll survive.
Hopefully someone will take up a study on this problem, which will benefit us all in the long run. I don't have a controlled enough environment (or the room) otherwise I'd look into taking it up myself.

As of 9:15 PST both maximas are still looking good... we'll see how the next few days go.

[Barry N.]

On a final note, it's still up in the air as to whether this disease is transmitted clam-to-clam, or if in fact it is an opportunistic parasite brought into the reef from another organism.
The way the parasite kills the host is by preventing mantle extension and starving the clam.

We have done some little test with this and like you say, it will starve the clam in time. We placed one of these infected clams in a 20 gal tank with another clam that appeared to be healthy and in 2 weeks the infected one died, the healthy one is still doing well. There is SO much we still don't know about the awesome animals.