Clams - pinched mantles

[aesop]

Out of the 5 maximas I had - the one that was never "infected" died from the dip (shortly after). The rest made it through fine.

To this day two other clams (smaller 2-3" ones) died due my tank being "all messed up". So it looks like a freshwater dipped is the "cure" for this disease.

 

[odoprelude]

okay, quick question to you all.. I have a squamosa clam that is about 7 inches long and a crocea clam that is about 4-4.5 inches. I've had these guys for about 7 mos now and had to move them recently... funny thing is I noticed some pinching (I think) before I moved them and am noticing less now. Here's the situation. I have dual 250's with 10,000k on for about six hours a day and then I run my 110w pc's for the rest of the 12 hr photoperiod. When the halides are on man, do these puppies open up, but of course when just the pc's are on they shrink up. Does pinching occur when under full lights or will it show up under less lighting? This may be a dumb question, but I figured you guys could help! Thanks!

 

[OrionN]

With this disease, the clams open up more in AM and the pinching got worst as the day goes on. They looks worst in evenning just before the light go out.
Normally, clams will retract as the light go out because they they only extended their mantle to collect light, so I think your clams is fine.
Minh

 

[piercho]

I treated 3 clams with 2 showing typical signs of infection. On one, a Squamosa, the pinching was very advanced and it had a hard time recovering from the dip. It gapped so bad afterwards I assumed it was a loss. But I kept it in a q-tank and fed it DT's for several weeks and it eventually began to look normal again. I think that it gulped a fresh water while being dipped, did some damage to its internals, and this led to the gapping.

All three clams are with me over a year later with no sign of re-infection and I would like to thank Minh for the personal help he gave me when I was deciding whether to dip. The squamosa is now the fastest growing of the three clams.

and it would be pretty expensive to set up a quarantine tank for a crocea since metal halides would be a must.

I used just a bare 10G tank with a power filter to hold that sick squamosa for several weeks. I'd change half the water weekly. I lifted it up close to a white PC lamp with eggcrate and fed DT's. It survived and grew, with no change of mantle color. Never done it to crocea, done it like this for a couple of weeks for maximas. I'm not convinced that q-tanking clams is as difficult as it is generally assumed it is.

 

[Reefcherie]

Sunday I dipped all 8 of my clams because two were pinching very badly and a third had started. I dipped for 30 minutes and did bring the pH up a little from straight RO water, along with exactly matching the clam tank temperature. The small teardrop clam really looked like a gonner before doing this. They all opened again within a half hour of stopping the dip - only one gaped at all. Today, they look terrific w/ the exception of the squamosa which still is showing a little less mantle than before, but it isn't gaping at all. The little teardrop now looks like a survivor and the other that was pinching badly now looks perfect! I don't know if this will last, but I'm sold on the process!

Cheri

 

[OrionN]

I was asked why I think this is a disease by PM. I though that I post the answer here so I don't have to keep on write the same thing over and over.

I keep clams for a while now and can see when they are not well. I fought with this disease for over 1 year. There are many reasons for a clam to retract their mantles. There must be other disease out there that bother clams, and will cause their mantles to retracted. However, the mantle retraction due to Pinched Mantle Disease (PMD) is unique. The following are what I consider specific characteristics for PMD:

1. There is no visible cause of irritation to the mantle of the clam.
2. The retraction is at the same place day after day and spreading to adjacent part of the mantle. In tank that is heavy infested with the disease, a clam can have several area on the mantel that retracted at the same time.
3. This is a slow infection. Larger, healthier clams can last for months. Weaker clams can succumb to this disease in days to weeks.
4. The retraction is less in AM and worst in PM. There is often mucus threats in the area of the retracted mantles.
5. The spread of the disease is often proximity. Nearer clams get infected much quicker than clams farther away.
6. Early infection can be asymptomatic.

This disease can be easily treat with fresh water dip for 30 minutes (maybe less) I have never try to dip for less time. Treatment is (much) more effective if the clam is remove and place in a new, disease free tank (100% effective if the clam is put in a new tank). Treatment can be effective if treat and return to the same tank if all clams are treat at the same time. This is likely due to the fact that early infection is asymptomatic and the pathogen seem to be obligate to live on clam with short host free period (This is my guess)
Goodluck to everybody with this disease in their tank.

Minh

 

[Reefcherie]

I am interested in this statement:

There is often mucus threats in the area of the retracted mantles.

I noticed large quantities of nasty looking (clear to clear w/ debris in it), thick, jelly-like mucus in that clam tank - none in the other tank that has two clams and no pinching. Do you think the clam is producing this in response to the disease? I hate the look of the mucus but didn't know if I should attempt to remove it with a turkey baster or not....

Cheri

 

[OrionN]

Cheri,
IMO, the mucus is just produced by the clams in response to the irritation. I have never try to remove it or get it out of the tank.
Minh

 

[Barry N.]

Mucus secretion can also be caused by fish coming in contact with the clams upper edge and if the fish continues the clam will secret mucus.

Am sure it will also produce mucus when the mantle become irritated by something.

 

[Reefcherie]

Mucus secretion can also be caused by fish coming in contact with the clams upper edge and if the fish continues the clam will secret mucus.

Am sure it will also produce mucus when the mantle become irritated by something.

Hmmm - in this case there were no fish in the clam tank, but it appears the disease was/is in there and the clams w/ the most pinching had the most mucus. In the 180, with a full compliment of fish - no pinching and no mucus.

Just observations at this point. I'd love to have someone do some scientific work to try to identify what is at work here - a bacteria? What is the freshwater killing?

Cheri

 

[Barry N.]

Cheri, I was just conveying that mucus can also be caused by more than what has been said.

We have done a lot of trial and error with this topic in the past 9 months but the verdict is till out with our test.

This is what we have found at the bottom of the container where we did some FWD. Something's have been identified but some have not.

 

[Reefcherie]

Looks similar to what I found, but probably only 2 or 3 of those Asterina starfish with 8 clams having been dipped.

My "data" concurs with Minh's in that of the eight, the problem was first seen in the smallest clam - a 2.5" teardrop, then spread to the same sized Crocea clam next to it. The only other clam starting to pinch a little was a 3.5" Crocea not that nearby. The clam next closest to the two little ones was a big Maxima.

Cheri

 

[jamal-188]

I have had a 3" maxima in my tank for about 7-8 months that has shown great growth. On saturday I purchased a 5" cocea and a 5" maxima. The maxima has not opened much since I've gotten him and the maxiam I've had has started showing signs of pnching so I"m assuming that with one of the new clams came the disease. I'm guess I should remove all 3 and dip them in FW for 30mins, the only problem is the maxima I've had it attached to a rather large rock, should I try to dip the entire rock or try to remove him?

 

[zrograviti]

2 out of my 3 maximas are having the same problem. I guess I'll try fresh water dip. So, use fresh RO water and add Kalk wax to get right ph, and heat the water to the tank temp then dip for 1 entire hour, right?? (scary).. anything else to add? I also have another problem. these maximas are about 2" and are attached to rocks. Is it ok to slowly pull them off or is there some better method to pull them off?

 

[Reefcherie]

30 minutes - not an entire hour!! You can't just pull them off the rocks if they are attached - that would be very bad! If they are on small rocks, I'd leave them attached and put the entire rock in the freshwater dip (that is what I did). If the rocks can't be taken out of the tank or are very large, you would have to cut the byssal threads. Gently rock the clam until you can see the threads, and then cut them next to the rock with a new razor blade or sharp scissors. You must be careful not to cut the clam's foot.

Cheri

 

[clsund]

Minh, my clams have been exhibiting the pinching as well. I did a FW dip in RO water yesterday for 30 minutes. However, two clams are still exhibiting the pinching today. Should I do the dip again? The other clams I have look fine. And I also fed them after the dip.

 

[OrionN]

Minh, my clams have been exhibiting the pinching as well. I did a FW dip in RO water yesterday for 30 minutes. However, two clams are still exhibiting the pinching today. Should I do the dip again? The other clams I have look fine. And I also fed them after the dip.

I would watch them for now. Wait a week or two and see how they do. FW dip is very stressful for sick clams

 

[sahin]

Minh: My derasa clam had the pinching mantle disease about 7 months ago. I carried out the frshwater dip @ 30mins initially. The clam was ok for about 3 days and started to pinch again. I then dipped it again for 30 mins. Since then the clam has been fine. The clam is the only one in my tank for the time being. Its been 6 months and its doing great. I am hoping to buy another clam in a few months time.

One thing I did notice that smaller clam (1-3inches etc) dont make it if they get the mantle disease, whereas larger clams do much better and have a better chance of survival. I lost 3 small clams in the past.

I only plan to buy larger specimens from now on.

I dont know, but somehow it seems there are less cases of this disease these days?

 

[Vili_Shark]

Sahin,
I read that in the Singapore reef club they been losing clams lately.

I just dipped my clams too.
I found two Pyramid snails over my clams, but I dont think that two can cause them to pinch.

 

[jamal-188]

I dipped my 3 clams tonight, I matched temp and pH. They starting opening almost right after placing them back in my tank but they seem to still be pinching, will this hopefully clear up in the next few days or didn't the dip work? I figured they'd be stressed and not open for a while and hopefully when they decided to open they wouldn't be pinching anymore.

Thanks
Chris