skinz78
10K Club member
Over the years I have seen lots of clams with pinched mantle "PM" and have helped countless hobbyists treat their clams to rid the PM. I figure it is time to post this article about what I have found to cause or "trigger" PM and what options there are for treating it. This is just my observations and there isn't any scientific proof to back my findings, just what I have seen work time in and time out.
So what is pinched mantle disease?
Pinched mantle disease is caused by a protozoan that can be deadly to clams if not treated properly. Back in 2009 - 20010 when Clams Direct was still under the ownership of Barry Neigut there was a study done on PM, mostly paid for by fellow hobbyists and the cause was pinpointed on the Perkinsus protozoan. You can read the full study written by Dr. David Basti, Deborah Bouchard and Barry Neigut here: Pinched Mantle Syndrome in Giant Clams.
What does pinched mantle disease look like?
This is one of my clams that I have had that had pinched mantle disease. You'll notice that the mantle is scrunched up and often rolled inwards in a pinched fashion.
Causes of pinched mantle disease.
Pinched mantle disease can be triggered by many different things, but basically anything causing stress is a main factor. Many of the clams that we currently have in our home aquariums have the Perkinsus protozoan in them. But it is dormant just like our fish have the Ich dormant inside them too. Around 2005 to 2009 the clam market was flooded with Crocea's and Maxima's that were coming out of Vietnam and had PM wreaking havoc inside of them when they hit our tanks. This was due to poor collection and quarantine practices before they even hit the ground in the USA. Since then, the practices seem to have changed and it is fairly rare to see a clam with pinched mantle being offered for sale.
Once clams have been added to the home aquarium is when I've noticed that today's PM problems begin to occur. Improper acclimation to water parameters, water flow, and lighting intensities, fish and inverts who have developed a taste for clams, the use of Granular Ferric Oxide "GFO", and any other cause of stress to a clam can trigger the PM.
My tried and true method of treating pinched mantle disease.
Over the years, reef enthusiasts have learned the common misconception that the only way to treat PMD is with a twenty min fresh water dip. This is not true and more often than not you will cause more harm than good. A fresh water dip is extremely stressful and should only be done as a last resort.
My first step to treating PM is try and see what is triggering it and then remove the trigger. IE: if you have GFO, a nipping fish, stinging coral, etc remove it ASAP. Once that has been done I highly recommend running as much carbon as you are able to and push as much flow through it as you can. Once carbon is running, I change mine out every two days during the first week of treatment. After that, I change it every four days till the PM is no longer present. If running carbon doesn't make a change in appearance of the clam in one weeks time then I recommend doing a twenty min fresh water dip.
When I do a fresh water dip, all I do is take a bowl full of new RO/DI water, float it in the tank for ten to twenty minutes to equalize the temperature. Once the temperature is the same as the display tank's water, I place the clam fully submerged in the bowl of fresh water. Over the next fifteen to twenty minutes, I gently use a turkey baster and blow the water all over the clam to ensure a good washing of fresh water. Once done, I place the clam back into the display tank in the lowest stress location I can find.
I hope you have found this article helpful and if you have any further questions, please post them up and I and others will help where we can.
So what is pinched mantle disease?
Pinched mantle disease is caused by a protozoan that can be deadly to clams if not treated properly. Back in 2009 - 20010 when Clams Direct was still under the ownership of Barry Neigut there was a study done on PM, mostly paid for by fellow hobbyists and the cause was pinpointed on the Perkinsus protozoan. You can read the full study written by Dr. David Basti, Deborah Bouchard and Barry Neigut here: Pinched Mantle Syndrome in Giant Clams.
What does pinched mantle disease look like?
This is one of my clams that I have had that had pinched mantle disease. You'll notice that the mantle is scrunched up and often rolled inwards in a pinched fashion.
Causes of pinched mantle disease.
Pinched mantle disease can be triggered by many different things, but basically anything causing stress is a main factor. Many of the clams that we currently have in our home aquariums have the Perkinsus protozoan in them. But it is dormant just like our fish have the Ich dormant inside them too. Around 2005 to 2009 the clam market was flooded with Crocea's and Maxima's that were coming out of Vietnam and had PM wreaking havoc inside of them when they hit our tanks. This was due to poor collection and quarantine practices before they even hit the ground in the USA. Since then, the practices seem to have changed and it is fairly rare to see a clam with pinched mantle being offered for sale.
Once clams have been added to the home aquarium is when I've noticed that today's PM problems begin to occur. Improper acclimation to water parameters, water flow, and lighting intensities, fish and inverts who have developed a taste for clams, the use of Granular Ferric Oxide "GFO", and any other cause of stress to a clam can trigger the PM.
My tried and true method of treating pinched mantle disease.
Over the years, reef enthusiasts have learned the common misconception that the only way to treat PMD is with a twenty min fresh water dip. This is not true and more often than not you will cause more harm than good. A fresh water dip is extremely stressful and should only be done as a last resort.
My first step to treating PM is try and see what is triggering it and then remove the trigger. IE: if you have GFO, a nipping fish, stinging coral, etc remove it ASAP. Once that has been done I highly recommend running as much carbon as you are able to and push as much flow through it as you can. Once carbon is running, I change mine out every two days during the first week of treatment. After that, I change it every four days till the PM is no longer present. If running carbon doesn't make a change in appearance of the clam in one weeks time then I recommend doing a twenty min fresh water dip.
When I do a fresh water dip, all I do is take a bowl full of new RO/DI water, float it in the tank for ten to twenty minutes to equalize the temperature. Once the temperature is the same as the display tank's water, I place the clam fully submerged in the bowl of fresh water. Over the next fifteen to twenty minutes, I gently use a turkey baster and blow the water all over the clam to ensure a good washing of fresh water. Once done, I place the clam back into the display tank in the lowest stress location I can find.
I hope you have found this article helpful and if you have any further questions, please post them up and I and others will help where we can.
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but he almost seemed to like it.
