ever seen PINCHED clam mantles??

[brad789]

i'd like to get a discussion going on a condition that possibly contributes to or is a symtom of something causing clam death. minh nguyen has a thread going on over at reefs.org about it, with pics ... http://reefs.org/phpBB2/viewtopic.php?p=169654#169654

i have seen a similar condition with my clams. i have lost a 4" squamosa which, over a period of 4 weeks, the mantle became more and more pinched. i have a 3" crocea that i've had for two months that off and on has shown some pinching. i have a new 5" maxima of two weeks that is now showing some of this pinching. i have a 4"derasa that's been in my tank for 6 mos that has never showed this pinching. in all cases, the pinching on the crocea, maxima, and lost squamosa began near the incurrent syphon along the mantle where the mantle meets the shell. all clams have also shown new growth (especially the squamosa) prior to the pinching. my tank has been stable for several months now, i have good lighting, and chemistry is all in line according to recognized authors and fellow reefers.

does anyone know anything about this? what can i do to help out my crocea and maxima? minh nguyen used a 30 minute dip in fresh r/o. anyone else have experience dipping clams in freshwater?


brad

 

[texman]

You might as well try the dip - As I mentioned in Minh's post, I lost about 15 clams to that "condition" which I am not sure has been attributed to any particular organism yet. You will need to do something quick or else all your clams, including the healthy looking derasa, will soon perish from this condition.

 

[brad789]

texman-
did you follow the dipping method that minh used? what were your results?

 

[texman]

I am afraid that I did not know about it until it was too late. I did try several other tings inckluding medications, but none worked for me.

 

[Minh Nguyen]

I posted this over at reefland.com and like to paste it here. Thanks

Guys and gals,
I just wanted to say that my blue clam pictured above was not cause by trauma, sting by corals, attack by fish or parasitic snails. I know how to keep clams. The two clams shown I have had for 2+ years and grew from 1.5 inches to over 3 inches. Water condition in my tank was optimal for clams and SPS. There was plenty of light.
I got this disease from trying to save a sick clam for a friend. I was cocky and think that the clams was not doing well because of water condition rather than disease.
Infected clam will show more extension of mantel in AM but less and the day go on. Initially, the mantle is local only (only on one segment of the mantel. As the disease progress, the whole mantle will get involved. This disease does not kill the clam quickly unless the clam started out in bad shape. IMO, it mainly kill because the clam unable to extend the mantle thus will not get enough light. It can take months for large clams and for small 1.5 inches, it can kills in weeks. My 18 inches Gigas was infected for about 1 year.
I was successfully treated all my infected clams. Please review the following thread (second page of the thread) for detail of the treatment:
http://www.reefs.org/phpBB2/viewtopic.php?t=21957
I do have one favor to ask of everyone who use the tratment I suggested. I would like for you to document the condition of your clams, the duration of infection, the course of the disease as you observed it in your clams, and the sucess or failure of treatment. I would like for you to send these result to me at:
[email protected]

Minh Nguyen


__________________

 

[simonh]

Infected clam will show more extension of mantel in AM but less and the day go on. Initially, the mantle is local only (only on one segment of the mantel. As the disease progress, the whole mantle will get involved. This disease does not kill the clam quickly unless the clam started out in bad shape. IMO, it mainly kill because the clam unable to extend the mantle thus will not get enough light. It can take months for large clams and for small 1.5 inches, it can kills in weeks.

I have been suffering this problem exactly as you describe for the last 12-18 months with most of my clams. I don't have any parasitic snails, have no problem with testable water paramaters, and have a tank full of fast growing Acropora in excellent health (the only 'problem' I have is some red flatworms). So far I have lost a few clams although most last out quite a few months until the mantle becomes so disfigured I feel they are inadequate at light gathering. I still have 4-5 remaining with the condition. All the clams have grown well before slowing growth when this problem occurs. I too notice the problem seems to get worse over the photoperiod. It has also frustated me so much I am glad to have found someone else who seems to describe the exact symptoms and progression of the problem that I have suffered!

I had noticed in my old tank that performing a large water change of 50% the clams would recover partially and expand more for a week or so before the problem would repeat. Based on this I thought the condition maybe due to buildup of something in the water even though everything a test kit could test for showed okay. They were then moved to my new tank (fresh SW) where they seemed to show reversal of the symptoms and good extension of the mantle (not full extension in all cases). However, after a few months here I go again. I did move 3 of the clams out to a quaranteen tank where they recovered... upon moving back to my main tank they started to show growth once again. Yipee! Now a few months later one or two are again showing symptoms

I did notice recently when doing a 60l water change that the symptoms again seem to be reversed for a few days. I started to wonder about depletion of something rather than accumulation. Based on the fact it does seem to develop worse further into the photoperiod I wondered if some sort of photo-oxidation taking place. I had a hypothesis been that maybe water change replaces iodine helping to recover them. Somehow a couple of weeks ago after dosing some additives that I haven't touched for alongtime and also a phytoplankton I noticed a reversal the next day in my worst affected clam. I have since been trying to isolate what if any of them caused a temporary recovery in the clam but so far haven't been able to repeat the reversal and the clam is proceeding to get worse. So I'm still scratching my head at what is causing it.

However, the fact that your have recovered the clams without any additions of additives just FW dips would seem to suggest something else at work. I may try your treatment described in the other post on my clams and photo document the clam before and afterwards.

How long is it since you treated the clams?

How long were the clams kept in quaranteen?
_________________
full melt

 

[texman]

Simon,

I tend to feel the same way about this problem as Minh, in that the problem is due to some kind of organism. When I had the problem, I bought test kits for everything that can be tested for and made absolutely sure that I had no large predators, but the clams kept dying. One thing that I find to be very strange is that whatever it is, seems to move from one clam to the next. This sounds more like a large vector such as a crab, worm, snail etc, although I never found one. In a typical infectious outbreak, either viral or bacterial, one should see an exponential increase in the number of orgnisms infected (ie 1 then 2, then 4 ...) In my case, and very similarly in Minh's as it sounds, the clams seem to die one at a time. If there were a viral or bacterial infection involved, there must be some other vector other than water, which spreads the disease. Maybe some animal with a very short life span picks up the disease from a very sick clam, just before it dies, and then moves to a new clam and infects it. Perhaps this animal is a copepod or other small organism which only picks up the virus or bacteria when the clam is heavily infected. It then moves to another clam and infects it, and then dies itself. A water pollutant or chemical deficit should affect all the clams in the tank in the same way, and would not single out one or two clams at a time.

 

[Minh Nguyen]

How long is it since you treated the clams?

How long were the clams kept in quaranteen?

The last time I treated my clams was 3 months ago. I treated all my clams, even the ones that looks well. I only have 1 tank. I treated and put the clam back to my tank. I do not use a quarantine tank.
Minh

 

[simonh]

Thanks for the replies guys. It makes it more interesting that the clams were returned straight back to the main tank and did not show any further symptoms after treatment. One of the clams which I moved into a Q tank earlier in the year that fully recovered has shown no further symptoms after been moved back to the main tank for a couple of months, one of the clams which had nearly recovered with just partial pinching has steadily got worse again in the same time frame.

I need to schedule some time to setup a freshwater bath and follow your treatment protocol. I will photo document it.
_________________
Loratab Rehab Forum

 

[brad789]

this is a great discussion. two days ago i dipped my maxima. no more pinching, but time will tell if this works especially since i did not dip the other two clams. i have no idea what it is but the hypoteses presented here seem sound.

minh, so after three months are your clams looking as good as ever? i hope the condition does not return for you but if it does please alert us!

brad

 

[Minh Nguyen]

My clams look good after 3 months. I ordered 8 new Maxima two weeks ago. So far so good.
Minh Nguyen

 

[aesop]

I came across Minh's thread a little less then a week ago by accident. As it turns out I hade the same problem as what he had described.

Here is a thread that I started which described my problem.
http://reefcentral.com/vbulletin/showth ... did=129924

Minh confirmed through email that it looked the same as what he went through so I decided to dip my infected clams. (FW in same temp for 30mins).

Here are some pics after the dipping. They didn't extend as much as before; but they are improving from the looks of it. A third (the smallest) clam which is shown at the pbase site recovered right away (strange since he was dipped with the blackish one)

http://www.pbase.com/cowboy_coder/gallery/pinched_clams

Thanks for the replies guys. It makes it more interesting that the clams were returned straight back to the main tank and did not show any further symptoms after treatment. One of the clams which I moved into a Q tank earlier in the year that fully recovered has shown no further symptoms after been moved back to the main tank for a couple of months, one of the clams which had nearly recovered with just partial pinching has steadily got worse again in the same time frame.

I need to schedule some time to setup a freshwater bath and follow your treatment protocol. I will photo document it.

 

[Minh Nguyen]

It have been a few days since treatment. How are the clams?
Minh

 

[brad789]

here's my update....

my maxima has not shown pinching. he gaped for two days afterward and his color was very drab. it's been almost a week since his dip and his color is beginning to come back. keep your fingers crossed. since the maxima was working out well i decided to dip the crocea since it was beginning to pinch again. this was three days ago. the crocea took it well but his color is not at intense as it used to be. i'm sure he'll follow the same route as the maxima and color up nicely in a few days. i just hope the pinching stops.

brad

 

[Minh Nguyen]

If I am worry about the stress for the clams, I would dip them less than 30 min rather than using RO water mix with tank water. It is my OPINION that the infection is caused by microscopic parasites. Being small, it may take less than 30 minutes of fresh water to kill them.
I did not have mortality (only one death) with dipping for 30 minutes so I did not try to dip them for a shorter periord of time.
Good luck to everybody who have clams infected with this disease.
Minh Nguyen