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FAQs about Giant Clam Disease, Pests & Predators 4

Related Articles: Tridacnid Health: Pinched Mantle Syndrome in Giant Clams by Dr. David Basti, Deborah Bouchard & Barry Neigut, Example Chapter from NMA Reef Invertebrates book, on Giant Clams, Tridacnids, A Brief Guide to the Selection and Placement of Tridacnid Clams by Barry Neigut, Bivalves, Mollusks, Lighting Marine Invertebrates

Related FAQs: Tridacnid Disease 1, Tridacnid Disease 2, Tridacnid Disease 3, Tridacnid Health 5, Tridacnid Disease 6, Tridacnid Disease 7, Tridacnid Disease 8, & Pest Snails (Pyramidellids...),
FAQs on Giant Clam Disease by Category: Diagnosis, Environmental, Nutritional, Social, Trauma, Pathogenic, Treatments

Tridacnid Identification, Tridacnid Selection, Tridacnid Compatibility, Tridacnid Systems, Tridacnid Lighting, Tridacnid Placement, Tridacnid Feeding, Tridacnid Reproduction, Tridacnids 1, Tridacnids 2, Tridacnids 3, Tridacnids 4, Tridacnid Clam BusinessBivalves, Bivalves 2, Lighting Marine Invertebrates,

Aiptasia on Derasa Clam 9/6/07 Hello, <Hi Chad, Mich here.> I have recently acquired a Derasa Clam (2-3 in). <Little.><<A bad, too-small starting size... RMF>> It has not been fully extending its mantle for about 2 days. <Not good.> I checked with a flashlight for Pyramidellid but couldn't see any. Instead I found an small Aiptasia anemone on his shell. <This may explain.> Do you suggest lemon juice or something different? <I think I would try to manually remove, you may just be able to scrape it off the clams' shell. I would be hesitant to use any acids or bases here.> It is a 30 gallon tank so no Butterflies! <No.> Thanks Chad <Welcome, Mich>

Fallowing tank for clam, Pinch Mantle Disease   9/2/07 Hi Crew/Barry: <Eric> I would like to know, in order to get rid of the pinched mantle in my tank, will fallowing the main system work? If so for how long do need to do this? I have read the book Giant Clams in the Sea & Aquarium by James Fatherree. And in there he did mention that FW dips and some antibiotics do work. What do I need to do to actually get rid of the disease in my system? <Perhaps just leave it running sans Tridacnids for a few months> I believed Barry had an episode in his business and I have read the entire thread in reef central/reefs.org. I would like to see if either of you can help me out here. <I will Cc him here re> I currently have about 10 clams in my systems, 3 of them are Croceas. And they are affected the most, the Deresa, Squamosa, Gigas and Maximas are all fine at this point. Please help Sincerely. Eric. <Bob Fenner>
Re: Fallowing tank for clam.
  9/2/07 Hi Eric, I did respond to you, I think yesterday. Like I said, I would fresh water dip all the infected Tridacnids and do some major water changes. You may or may not know that we have been working with this problem for a few years and we have now identified the parasite. About 4 months ago, the University of Maine, Aquatic Animal Health Lab has been working with us, and when all our test are done, we will publish a paper on results either on a online magazine or FAMA. The "Pinched Mantle" problem has been around for about 5 years now and we have been contacted by aquarist from all over the world and we have gathered a lot of information that has helped. This thread may be helpful to you. http://www.clamsdirect.com/forum/viewtopic.php?t=1982 Cheers, Barry www.clamsdirect.com <Thanks Bar. BobF>

Clam and Bristleworm, comp.    7/13/07 Hello WetWeb, I noticed that my clam was not opening up like it usually does so I checked it out and saw a Bristleworm inside of the clam next to the byssal opening. However, it is in a very tight spot and don't have anything small enough to grab it. What can I do about this? Will my clam survive? <Oh dear, it sounds like your clam might be dead. How long has it been since it opened up? The vast majority of bristle worms are scavengers. They show up when something dies or is dying. Chances are that the bristle worm is not there to kill the clam, but is there because the clam is already dead or dying. Sorry :( Sara M.> Mike
Re: Clam and Bristleworm, comp.  
  7/13/07 The clam was very healthy prior to me finding the worm. <The bristle worms will almost always know when your clam is dead/dying well before you do. But ok, if you insist on suspecting the worm, there are worms from the family Oenonidae that eat clams. They drill holes into their victims to get inside them. You said the worm was "inside of the clam next to the byssal opening." That makes me think it's a scavenger, not a predator. But, if you do find a hole drilled into the side of the clam, you might actually be dealing with a clam worm. If that's the case, you can try to lure out the worm with some defrosted clam or mussel meat. They're nocturnal, so it would be best to do this in the very early morning before lights on and try to catch it with the help of a flashlight. Good luck, Sara M.>

Gigas clam health failing!!!!!!!!!!!!    5/12/07 Hello Bob & WWM crew, <Antonio> I have an 18in. Gigas clam that I bought 5 days ago. <Wowzah! I guess/hope you have/had a strong back!> I acclimated the clam well & placed him in my 150 gallon reef,  (48x24x30)! Water parameters are fine, PH 7.8(Which I wondered if it was too low), <Yes> and no other traceable problems in water quality. <Actually... whatever would occasion/cause the pH of this system to be this low is VERY big trouble> This tank also houses 9 other Tridacna clams, 13in. derasa, 10in. derasa, 8in. derasa, & a few others, squamosa(2), blue maxima, and one crocea. <... I would NOT mix all these species together...> The lights are 2 250W 6500K Iwasaki's, 1 175W 10,000K Red Sea bulbs! The new gigas clams mantle is starting to recede which I know from experience is a sign of impending death. His reflexes are still very good but I  can see clearly that he's on his way out! <Mmm, not necessarily... Is very likely still adjusting from the move...> Do you all have any clue as to what the problem may be? Antonio <Is/was this animal wild-collected at this size? I do hope not... If it was moved from someone else's system you need to talk with them, compare notes re feeding, water quality, light quality/intensity... For review, please read here: http://www.wetwebmedia.com/BookMatters/WWM/NMA-RI/NMA-RI_Tridacnids-demo.pdf and here: http://www.wetwebmedia.com/tridacnidart.htm for the links to the files above on Systems, Diseases of Tridacnids. Bob Fenner>

Unhappy Tridacna squamosa...Too Much Light Too Fast? -- 05/09/07 Hello, <<Howdy>> I purchased a 5 year old Squamosa (about 6-inches) approx 7 days ago.  I  did a two-hour drip and it acclimated very well for the first day.  The  second & third day it didn't want to open much, so on the fourth day I gently nestled a rock under it so it could foot hold. Almost immediately it opened up beautifully for about two days.  Now yesterday and today it is gaping on and off and the interior of the clam seems sunken in. <<Mmm...>> It is open and the mantel is out and the clam is very  responsive. <<A good sign>> Also the color looks good.  Is it doomed or can I do anything? <<Theirs is usually little we as hobbyists can do for these creatures once they show signs of decline, but if the decline is attributable to an environmental situation that can be identified and corrected  the clam may pull through if not too damaged/too far gone>> It was raised under VHO lights and is now is in a 75 gallon with 2 250-watt metal halides. <Ah!  A definite clue...  If the clam was not acclimated to the more intense lighting it is likely suffering from photo-shock.  You can try shading the clam a bit with layers of fiberglass window screen or the like (have a read here and beyond for more info: http://www.wetwebmedia.com/acclimcoralslight.htm), removing a layer every couple days to allow the clam to become accustomed to the new lighting...though since it has been more than a week since the clam was placed under the halides, this strategy may now be a moot point>> Ammonia 0 Nitrite 0 Nitrate <5  Phosphates 0 PH 8.4 SG 1.024.  I have a lot of sensitive corals like Alveopora and  a Crocea and Maxima and they are well so I don't believe it is the water. <<Then is likely the lighting>> Its bottom dwelling neighbors are a 3 plate Fungia  about 3-5 inches away and the other side a Lobo about 4 inches away.   Any help would be great. <<Do also have a read of this article by Barry Neigut of Clams Direct on selection and placement of Tridacnid clams (http://www.wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm ).  Regards, EricR>>

Maxima Clam and Shrimp - 4/29/07 Hello Crew! <Hi Brandon!> I work at a small LFS and we just got a few clams in. One of them (a gold teardrop maxima) is about three inches long and has a shrimp living inside of it. The shrimp is a white-gray color with small black polka dots all over it. It's about 1/2" long and it's pinchers seem to be large in proportion to its body. Not large like a coral banded shrimp but long and skinny and are held out straight in front of the head. The shrimp is hanging out inside the clam around the gills. I wouldn't be too concerned about it except for the fact that the clam is gaping a bit and seems uncomfortable with the situation. Any ideas what kind of shrimp it may be (I can try to get a picture of it but it should be difficult), and how in the world could I get it out if it is possible to? <Hmmm, I've heard of these shrimp, but unfortunately, I'm not sure which species it is. It also seems unsure whether these are parasitic or actually commensal. Please see this link for more information: http://www.wetwebmedia.com/tridacnidfaq3.htm . Also, I know it would be a challenge to photograph, but if you're able to get a good shot of this little guy, please let us know!> Thank you for your help, Brandon <You're very welcome! --Lynn> <<Is a commensal... no worries. RMF>>

Clam pinched   2/22/07 Ok, this is going to sound really odd but I was moving a rock and an Asterina starfish fell. It fell onto my T. Crocea clam. The problem is the clam is pinched and closed up in the area where it is. The rest of the clams mantle is out but its closed where the starfish is. What should I do? I cant get the starfish out now because I cant see it.       Thanks   Kevin <Mmm... am torn between suggesting leaving the two alone, and possibly moving/placing the Clam on its edge so the star is likely to fall out... I would do this latter if the clam does not re-open completely in a few days. Bob Fenner>
Re: Clam pinched cont.   2/22/07
ok today the clam is opening up a little more but it appears there is a hole there. So now it appears the clam has 3 holes. this is in the center so am guessing the starfish ate through him? If this is the case would the clam live and heal over.     thanks   Kevin <Likely so. BobF>

Sick Derasa Clam  2/18/07 Hello WWM crew!! <Darrell> I cannot express to you how much your site has helped me out in the last couple of months with researching this very addictive hobby. <Ahh, always a pleasure to read, realize> I spend about 3 hours a night researching and getting ideas from the over abundance of information here. Thank you all so much for all of the work you do and the knowledge/experience you share with us. A million thanks. Now for my problem'¦ <Welcome> I have a 29 gal reef tank with a Millennium 2000 filter, a HOT Magnum Canister filter which contains Nitrate sponge (you'll understand why in a minute) and an Aquarium Systems SeaClone 100 Protein Skimmer (which is impossible to keep adjusted correctly). <Yikes... it's not just you...> The tank has been set up since April 2006 and has done exceptionally well in that time. It contains around 45-50 lbs of live rock and 40 lbs of live sand (approx. 1-1.5' sand bed). My lighting consists of (2) 65W PCs and a 125W HQI, the PCs run for 10 hrs a day and the HQI is on for 8 hrs per day. <With no vacillating heat problem?> I have never had an algae problem so I am wondering if I should increase the photo period for the clams/corals. <Mmm, maybe... what do they look like?> My chemical parameters are pretty consistent and as of yesterday are as follows; PH -- 8.2 Ammonia - 0 Nitrites - 0 Nitrates - 30-40 (I'm fixing that problem now with a refugium and more frequent water changes) <Good approach> Phosphates - 0 Calcium - 470 <A bit high... I'd allow this to drift to 350-400 ppm.> KH - 9.9 Magnesium - 1320 Alk - 3.54 I am currently cycling my 75 gal tank which I have just converted from FW and I just finished the sump and refugium construction which your site was an invaluable tool for understanding and designing and it seems to be working perfectly. <Ah, good> I am planning on using a DSB in the refugium with some macroalgae to help with Nitrates and bugs. I have around 70 lbs of dead rock to which I will be adding another 20 lbs of live rock this week. I plan on also having around 1 inch of live sand in the tank (unless you would suggest otherwise). <Mmm, no... this is about right> This, I hope, will alleviate the Nitrate problem I am experiencing in my 29 gal. <Very likely so> OK, now that that's out of the way, my main concern. I have a Crocea and a Derasa and my Crocea has been in the tank for about 6 months and is doing wonderfully. My Derasa on the other hand is not looking very good at all. It was added about 2 months ago and approximately 2 weeks after adding it the mantle started to appear to be 'scratched'. <I see this> I thought maybe my hermits were walking over it or something so I moved it to a protected area of the tank and it doesn't seem to be improving. <Takes time...> It will react to shadows and will open partially but will no longer open fully and the mantle never extends past the shell. I will include a pic of the 'scratched mantle' for you to see. I have searched all over the internet and your site and the only thing that comes close is the pinched mantle disease but this doesn't seem to be the case here <No> although I could definitely be wrong. I am very naive when it comes to marine diseases. The other tank occupants are a 4 stripe Damsel, Yellow Tail Damsel, Coral Beauty, Clown (Percula I believe), (2) Sally Light Foots, (3) Porcelain Crabs, Emerald Crab, 6 or so Hermits, Snails and several species of corals. <Mmm...> I have examined it many times for Pyramid Snails and have never seen even 1. <Look at the base... the byssus... if/when moving to the new, larger system> If you have any other suggestions, <... Do you feed your sessile invertebrates? Amend same with supplementation? I would> they would be eagerly accepted. I am sorry if this is long winded but I wanted to give you as much info as possible. Thank you again for everything you guys do for the Aquatic community, it is greatly appreciated and highly valued. Darrell West Chester, PA <Please do read the area over re Tridacnid nutrition: http://www.wetwebmedia.com/marind5_5.htm scroll down...> P.S. Thank You Mr. Fenner for The Conscientious Marine Aquarist, I purchased it a month or so ago and I just wanted to tell you, you did a great job. <Thank you my friend. Bob Fenner>

Tridacnid, Squamosa...Sorry We're Closed  2/1/07 Hi Guys - <Hi Jim, Mich with you today.> I am a new hobbyist that inherited a 50 gal tank. <Welcome to our salty world.> After eight months with no losses, last month I lost a small green clam (3 inches). I started noticing it with the Tang nipping at the mantle. After a few more days the clam was sick and it died a few more days later. <Sorry for your loss.  Is this tang still in you system?>   A week ago, a larger clam (5 inches) with a brown mantle took to not opening for most of the day (not gaping). I inspected for Priams. None. I did find a couple of small starfish outside, which I removed.   <Probably not the problem.> For the last two days, the clam has opened wide in the morning, but when something closes it (today it was an urchin crawling up onto it). It doesn't reopen for most of the rest of the day. For the last few days, I have moved it to inspect it. Afterward it will open and close hard a few times, like it's trying to expel something. Then it stays hard shut. I sure hope its not dying. When its open, it looks normal. <Gaping would be a bigger concern, though it doesn't sound happy.  Sounds like something is irritating it.  Clams will close when something bothers them.  Perhaps the tang is nipping at it?  How is your water temp.  Sometimes clams will close if the temp is out of sorts.>   I ran tests on the water. All seems ok. Water changes are small (5%) and frequent (weekly). I did notice that this all started after I started using Joe's Juice to fight an Aiptasia infestation. I don't use much, but it does burn the coralline. <This could be the source of irritation.  Are you still using it?> Any suggestions? <Mmm, stop using the Joe's Juice and perhaps leave the clam be for a while.  You may want to do a larger water change maybe 10-20% and see if you get any improvement.  Keep an eye on that tang.  It does sound like something is irritating this clam.>   Thanks, Jim <You're welcome,  -Mich>
Re: Tridacnid Squamosa...Sorry We're Closed    2/2/07
Thanks for the thoughtful reply. Yesterday, after thoroughly reading your site, I did a fresh water dip. The clam liked it. <Mmm, I'm not so sure.> Right after I put it back in the tank, as it was doing its expulsion routine, a small starfish (one-legger) appeared on the lip of the shell. I removed it. Don't know if the starfish was inside the clam or if I just missed it as I inspected it. <I guess either is a possibility.> Today the clam is open, although the edges of his mantle are curled. <Yeah, not so sure I would have done the freshwater dip.  Can lead to inflammation of the gills, and further stress this already unhappy clam.> We will see. <I do wish you the best here my friend.>   I would gladly stop using the Joe's juice. How do I keep the Aiptasia at bay? <Several possibilities.  I personally have used Peppermint Shrimp (Lysmata wurdemanni) and had success.  I found the key is these shrimp have to get pretty hungry before they will choose to eat the Aiptasia.  So this may or may not work for you, depending on what else is in your tank if it's possible to not feed your system for couple days without causing harm to the other inhabitants.  Kalk paste is another good option.   Please read here: http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/aiptasia/aiptasia.htm http://www.wetwebmedia.com/ca/cav1i3/aiptasia_impressions/aiptaisia_impressions.htm http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/aiptasia/aippepshrpfaqs.htm http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/aiptasia/aipcheminjfaqs.htm They seem to spring up as fast as I kill them. <They can be pesky little buggers!> Maybe there is a breeder way down among the rocks, but I can't find him without deconstructing the tank (and the sponges and other stuff have really grown, so I am reluctant to move everything). I have thought of shrimp or a copperhead, but I have an eel that is way cool.... <Oops never mind the shrimp, try the Kalk paste.>     Thanks again. Jim <Welcome!  -Mich>
Re: Tridacnid Squamosa...Sorry We're Closed   2/3/07
Hi Guys - <Hi there Jim, Mich here again!> Just an update. All yesterday the clam was open wide, and again this AM. <Oh!  Very good news!> Pulled two starfish off the other blue clam this AM. But everyone seems happy today. <I hope this happiness continues!> Thanks for your help and advise. <Welcome!  -Mich>

T. Crocea With picture inserted and quite large   1/11/07 Photo was attached; the one below my name is something part of the signature block.  I have attached it again in this replay Bryan <I see it now> Hello & Happy New Year, <Thank you B & K! >      I have recently added what I believe (99%) to be a T. crocea to my display after being kept in quarantine for about 2 months. <<Looks like this to us as well... smooth shell...> All around the clam looks excellent.  This is my first clam and final addition, so I did some research and followed Calfo and Fenner's Summary of care in Reef Invertebrates.  After two days in the display, it seems as if it is "gaping" a bit. <<Mmm, nah, not IMO>> I tried to set him just right in the tank; on top of a sand-covered rock, moderate current, 18" below the surface under 400 watts of PC lighting 10-20K.  It has moved slightly (rotated 15 degrees), and is very reactive to movement in tank.  The tank is well established, populated and the food source will be continue to be DT's live plankton and oyster eggs, calcium ranges from 450-500ppm and salinity 1.025.  I have attached a photo for your thoughts.  Would you consider this "gaping"? <<Nope>> Is their anything that I should consider doing or look for? Thanks, Bryan < http://www.wetwebmedia.com/faqstips.htm (post titled "How do I send a picture of identification to you???  3/20/06" <<I wouldn't be concerned here Bryan... all reads, looks well. BobF>>

Dead fish, toxic tank, moving livestock (Tridacna) ASAP    1/5/07 Dearest crew, <Hi Carla, Mich here.> Tragedy has struck, and this reader is frantic.  My initial hypothesis is that a powerhead in my tank jammed/overheated/otherwise malfunctioned, and my roommate called me at work saying there was an electrical burny smell in my bedroom, and she was afraid our apt. was burning down.  I instructed her to unplug the tank, and I'd be home in an hour... <Wise.> I returned to find two dead fish (and now one very dejected girl- I've had them for over a year). <So sorry.> However, as soon as my friend gets here to help me deal with the bodies (I'm squeamish... how is it that I can butcher a flounder without a second thought in the kitchen, but not scoop my little friends into a net? <Better to get them out ASAP as the bodies are just further polluting the system.> Because they were my little friends, I suppose. ANYWAY...) <Understandable, but not helping the remaining animals in your care.> My thoughts are now on the remaining Tridacna clam, mushroom polyps, hermit crabs, etc. still in the toxic water that killed my fish.   <Good thinking.> Luckily, I have another tank set up in my living room (was going to move them all to larger quarters...) which has been aging for a long while (several months... I'm a procrastinator... and the move task was daunting and now urgent). <Yep!> My main concern is this- the clam.  How can I move it, and the largish chunk of rock it's anchored itself to, into the new tank without either exposing it to air or introducing the deadly water from the old tank?   <Exposure to air will not kill your clam, though I would try to keep it to a minimum.  I would move the entire rock. Do not remove the clam from the rock. I repeat, do not remove the clam from the rock.  Place the rock and clam in a container with water from the contaminated tank and then add water from your new system.  Then dump some of the water and add more from the new system.  I would do this process relatively quickly, say within 30 minutes or so.  It's ok if a minimum amount of water from your old system is introduced; just try to minimize the volume.>   A response ASAP would be wonderful, as you can imagine I'm sweating over the fate of my remaining wet pets. *sniff* <Sorry for your loss.  It always hurts to lose a friend, in this case more than one.>   Thanks ever so much again, <Good luck and my condolences.  -Mich> Carla
Re: Dead fish, toxic tank, moving livestock (Tridacna) ASAP
   1/5/07 Thanks so much for your quick advice!   <Hi Carla, you are most welcome, sorry for you problems.> Blooper and Dex have been removed to bluer waters (i.e........ the dumpster) <Sorry about Dex and Blooper.  ...bluer isn't the adjective I was thinking of here!>   and I'm moving the live rock and following your clam transferal instructions.  Hadn't planned to remove the clam from his rock, but am relieved that I don't have to attempt some complicated plastic bag procedure/underwater move.  It's in a bucket next to the new tank, and I'm quickly but gradually mixing the water.   <Excellent.> Will let you know how things turn out!   <Please do, include my name in the subject line if you don't mind.> One of the powerheads was most certainly the culprit, as it smelled strongly of electrical burnout. <Happens.> Will it be safe to move some/all of the sand to the new tank, or will it contain residuals of whatever killed my fish (not sure if it was an electrical shock or a chemical contamination from the powerhead malfunction)?   <Hard to tell the cause, but I think I would wait on the sand transferal.  Do a couple of large, like 75% or more water changes.  It may be possible to transfer the sand, but I wouldn't do it anytime within the next month or so.  I would watch and see what kind of die off you experience within this tank and see if you get regrowth.  ...Though being a procrastinator maybe I should say sometime in the next two weeks so it happens sometime in the next couple of months...Hehehee!> I'd planned to combine the sand from the old and new tank to create a deep sandbed... would like to keep the old sand and its good critters if you think this would be wise.   <Yes, in general I think this is a good idea, but would be hesitant to do it immediately for fear of possible contamination.  At most I would take a cupful just to seed the new tank, this would allow for growth but minimizing potential complications in the new system.> I'll be changing the filter media (Fluval canister) for fresh carbon, Chemi-pure, phos-ban, and poly filters (if I have any left...).  Anything else I should keep an eye on?  Obviously testing the tank regularly for the next couple days/weeks would be a good idea... and crossing my fingers? <All these things, coupled with a large water change or two would be helpful.  Good luck!  -Mich>

Derasa Clam Doing Poorly - 11/07/06 Dear Bob, <<Eric here...Bob is out washing the gecko poop off the deck 'honest <grin>. (I'm visiting at his place in HI at the moment)>> I purchased a Derasa Clam back in mid September.  I placed it in my sand bed in my 240-gallon tank.  The tank is well established, it has been set up for over a year. <<Still "young" mate>> The tank filtration system consists of an EV-240 protein skimmer, wet/dry in a 50-gallon sump, a 50-gallon refugium, phosphate reactor, and 400 pounds of live rock.  I have the built in overflows that direct the water down into my refugium, which is full of Caulerpa, and then my refugium drains the water into my sump where it gets further processed. My sump and my refugium are two separate tanks but they are connected together.  Also I have water being directed into my wet/dry where it is processed prior to entering my skimmer.  The water is then picked up by my UV sterilizer in sump prior to being returned to tank. <<Sounds like a nice setup...though I question the use of the wet/dry and the UV "if" this is a reef system>> Inside tank I have a SEIO 1100 on one side of the tank and I have elbows on the returns that shoot the water into the middle...The SEIO just shoots water straight across.  I have a bunch of coral too that seems to be doing fantastic. <<Ah...so a reef tank it is...>> The fish that are in my tank are: Naso Tang Desjardin Sailfin Tang Yellow Tang Scopus Tang 3 true Perculas 1 mandarin 1 cleaner shrimp 1 blood shrimp Also have 300 hermit crabs and about 300 Nassarius vibrex snails.... My water quality is: pH 8.2 Ammonia - 0.0 Nitrite- 0.0 Nitrate 0-20 <<May not be a problem, but in reef systems I prefer to keep nitrate below 5ppm>> Magnesium- 1200ppm Alkalinity- 5.71 meq/l Calcium- 540ppm <<Alkalinity and calcium values are dangerously high (if accurate), you're flirting with a precipitous event>> Strontium- 7 Iodine- Not really readable <<Often the case...readily utilized/difficult to measure>> I use Salifert test kits to perform all tests on tank <<Fine kits>> Water quality was exactly the same when I introduced the clam back in September.  Lately I have noticed that the clam's mantle is not fully extending almost as if he is suffering from gaping. <<Mmm...>> I feed the clam once a week BioPlankton...(Tiny Bottle that you keep frozen).  Am I suppose to feed him more than once a week? <<First, let me ask...are you sure the clam actually "feeds" on this product?...I have my doubts.  It's likely the combination of lighting and your refugium provide the clam the nutrition it needs>> I keep him under a 175-watt halide, I have three on my tank.... <<Should be fine>> The tank is 2 feet deep and the lights sit about 16 inches above tank in a canopy. <<Hmm, awfully high...I would move these to within 10" of the water's surface>> I also have moon lights go on at night.  I recently read an article on your website about clams and it suggested to put a rock under the sand bed for it to grab on and also to keep it by just moderate current. <<Opinions vary...even here.  The rock is fine (some writers also believe this helps to keep predators away from the delicate byssal opening), but unless you're blasting the clam directly with a powerhead a heavy current won't mal-affect it>> I did just that and placed him upright on top of my sand bed with an oyster shell underneath the sand.  I also moved him to an area where he is protected from the current. <<Not necessary...even undesirable...in my opinion>> I put a rock on both sides so that he is well protected. <<This may be the problem>> What am I doing wrong and how are we going to save him?  Am I suppose to turn off UV when I feed him BioPlankton? <<I would turn off the UV altogether.  These units will destroy beneficial plankton/epiphytic matter generated from your refugium...maybe the clam is starving, BioPlankton or not>> When I feed him BioPlankton I put a few drops of the highly concentrated stuff into my water and unplug my skimmer for 8 hrs. <<Another unnecessary and undesirable habit, in my opinion of course>> Please help me..................... <<Were this me...I would remove the wet/dry and UV filters, get nitrates below 5ppm, lower the halides to within 10-12 inches of the water's surface, position the clam where it receives good light and water flow...and start reading here and among the associated links at the top of the page: http://www.wetwebmedia.com/tridacnidart.htm Sincerely, Christopher Faiola <<Regards, Eric Russell>> He was doing fantastic when I first put him in there .  What am I doing wrong and how do we save him? <<Consider my suggestions and read where I have indicated for further thoughts/ideas.  EricR>>
Re: Derasa Clam Doing Poorly - 11/22/06
Dear Eric, <<Hello Christopher>> After we spoke I did notice that the clam was doing well again. <<Very good>> It must have been something bothering it. <<Yes...many possibilities>> However recently it had some Aiptasia growing on it and I did remove it with Joes Juice.  The Aiptasia must have been bothering it because it started to gape again.  You know the feeding hole opened wide up toooooo wide. <<Not good...often a sign of stress>> However it still is very responsive to lighting conditions.  You know when you put your hand above the clam it's supposed to react and close rapidly and then reopen. <<Yes>> It does just that but the feeding hole has remained really large. <<Mmm...>> If you read through the previous email you will notice that the lighting was 16 inches from the top of the surface and the tank is 24 inches deep. <<I recall...and a bit "too high" in my opinion>> So it's a total of 40 inches distance because I originally had the clam placed on the very bottom of the tank. <<T. derasa is one of the lesser demanding species, but should still be provided with strong direct lighting.  Placing on the bottom of a 24" tall tank is fine...just bring those lights to within 8-12 inches of the water's surface>> In an effort to try to help him recover I have moved him so that he is only 20 inches from the lighting.  I placed him in a big oyster shell full of sand and set the shell with the clam on top of a flat rock. <<Should be fine if not "natural"...and all the handling is likely reason for the "gaping">> I also made sure that he is not getting blasted by my return pumps. <<Good>> What else can I do to get the clam back to perfect health? <<Leave it be for now and just "observe">> My water parameters now fit your criteria that you were talking about in the previous email. <<Very good, as I recall your nitrates were rather high.  Keep an eye on the clam and make sure you don't have a fish/shrimp bothering it (you may need to make a nocturnal visit or two to be sure), if water quality is as it should be and the clam hasn't been damaged otherwise it should recover fine.  Regards, EricR>>

Crocea Clam...Shell Going Soft - 09/28/06 Dear WWM, <<Dustin>> I have a 240 gallon reef tank which is 31" deep.  I have three 400 watt metal halides  (2 at 15K and the middle bulb at 20K).  I have a Crocea clam nestled in the sand bed at the bottom of the tank. <<Mmm, prefers a "rocky" perch.  A common name for this species of Tridacna is the "rock boring clam."  These clams exude a substance that softens carbonaceous material/rock, then by "squirming" about, they can actually bore in to the rock.  Not only is this more natural for the clam, but this action serves to protect their vulnerable byssal opening from predators/pests>> The clam seems to be doing fine but I noticed that the shell of the clam looks as if it is eroding. <<...!>> It is like it is turning soft towards the upper edges near the mantle. <<Can't be good...>> If I touch the shell it is soft and it just brushes away. <<Yikes!  Have never encountered this...pH/calcium/alkalinity are where they should be in this system?>> The clam still opens up but am not sure what could be wrong with its shell. <<Nor am I...>> My bulbs are only 3 months old and are still very bright. <<I don't think this is the problem>> Could it not be getting enough light? <<Something in the 10,000K range would be better in my opinion...but yes, it is likely getting enough light>> Or insufficient calcium. <<Mmm...just musing here, but I wonder if maybe something is keeping this clam from assimilating calcium from the water column?>> I have checked all my water parameters and they are all in sufficient range.  Maybe a fungus of some sort? <<Another possibility I suppose.  If so, I don't think there is much you can do as any treatment is likely to kill the clam>> Thanks so much, Dustin LeCave <<Wish I could be of more help...perhaps Bob/somebody else has seen this before.  Eric Russell>>

Crocea Death...Searching for Clues - 08/08/06 Hi Crew, <<Hello Jason!>> I just lost the first T. crocea clam I tried to keep in my system, and maybe you can help me diagnose the cause. <<Mmm, unfortunate...let's see if I can be of help...>> It had been in the display tank for about a month and a half, and until Saturday it was looking good (as in, I hadn't noticed any signs of trouble, though they may have been there). <<Indeed, but often with these clams it is too late by the time it is noticed that something is amiss.  And once they start to "go" they go quickly>> Saturday I noticed the mantle was not extending, and worse, the clam was not closing when my hogfish swam nearby, as it usually would. <<Mmm...a very bad sign...generally signals the end is near>> In fact, the hogfish poked its head into the clam! <<Yes...when opportunity knocks...>> Saturday night I did a 5-gallon water change (~65 gal tank including sump) and tested the water.  Undetected ammonia and nitrite, 10ppm nitrate, 0.03mg/L phosphate, 380 mg/L calcium, 8.1 pH, 1.022 salinity, 5.8dKH Alk.  Alk was clearly low, so I raised it a bit with baking soda to 6.2 dKH. <<Still a bit low, should be more than 7 dKH>> This morning, clam was closed. I left for the day, came back around midnight, and the clam was being eaten by a hermit crab. Most of its flesh was gone. <<Doesn't take long when scavengers are present...the flesh seems to be "relished" by all>> I inspected the shell for parasites and found none.  I also never saw worms bothering the clam, nor any inside the shell after I removed it. <<Their presence at this point would not have proven anything>> So, whodunit? <<Hmmm...likely environmental mate>> I am not inclined to believe it was lack of lighting, though tell me if I'm wrong.  I have 400W 20kK MH for my 58 gal display, and the clam was in direct light. <<As long as the clam was acclimated to the lighting and was not stressed/weakened by photo-shock then yes, probably not your lighting>> It did often seem pestered by my hogfish, however, and would frequently close up when the hogfish swam by. <<A stressor (the hogfish may even have been nipping at the clam), and likely a piece to the puzzle>> Thanks for any ideas and suggestions to avert future clam deaths! Jason <<Well Jason, there's no way to say with any certainty what caused the demise of your clam.  As stated previously, it was probably environmental...a combination of factors that may include excessive nitrates (clams do appreciate some measure of nitrate, but I would recommend this be kept below 5ppm), collection/shipping stress compounded by the attentions/pestering from the hogfish, out-of-balance earth elements (Alk), even a lower than NSW salinity (should be 1.025/.026).  Any of the elements/conditions on their own may not have been a problem, but when combined.......  And something else to consider.  You don't mention other corals in the system, but the presence of noxious organisms such as mushroom/soft/leather corals (Corallimorphs, Alcyoniids) can make keeping clams very difficult.  Increased water changes and chemical filtration (carbon/Poly-Filter) can help, but even then it sometimes is not enough.  Another consideration is that "dosing" in the vicinity of the clam may have poisoned it (especially iodine)...very efficient filter feeders.  All speculation on my part my friend...but some food for thought.  Regards, Eric Russell
Re: Crocea Death...Searching for Clues - 08/08/06
Thanks for the detailed reply! <<Quite welcome>> In fact, I do have a number of soft corals and mushrooms in my tank.  There is large cabbage leather (Sinularia dura I believe), a smaller Sinularia sp., three smallish mushrooms, a few stalks of xenia, green star polyps, and some Zoanthids. <<Mmm...but for the Xeniids, all are quite noxious (Sinularia is some of the worst)>> I did not realize these were incompatible with clams.  Is that a general rule of thumb, or are there certain clams that are better suited to being kept with soft corals? <<More of a "broad" statement...  Clams and soft corals can be kept together with provisions (low stocking density first and foremost), but in a soft coral dominated system you may find "long term" success difficult.  I'm not saying you can't be successful, but you will need to understand the challenge...and you "might" find T. derasa to be a bit more tolerant/hardy in this respect than the other species>> I also use Poly-filters and don't dose anything but a Kalk drip (in the sump). <<Do keep your calcium/alkalinity in balance...important to the clam>> I had let water changes slide for 3 weeks, which certainly did not help. <<Indeed...water changes are your single best tool for success here>> Thanks, Jason <<Always welcome, EricR>>>

Clam dip?   7/7/06 No, I'm not asking for your favorite clam dip recipe. <Heeeee!>   Is there a dip you can use for Tridacnid clams, similar to dips for fish and corals, before putting them in the tank? Thanks <Mmm, this could become quite a discussion... Some friends in the trade do have/practice rather elaborate acclimation processes for newly imported Tridacnids... But I would not do this as a hobbyist. I do encourage you to isolate/quarantine new purchases however, to investigate the presence of pests (esp. Pyramidellids) and assure health before placement in a main/display system. Bob Fenner>

Unidentified Clam Assailant - 06/27/06 Hi there, <<Howdy>> You've helped me before in the past with a freshwater problem I had, and now I got a new random question for you in the realm of salt water. <<Alrighty>> Yesterday, I noticed my Crocea Clam looked like it got knocked over, so I went to move it back in place, and noticed 2 things:  it's stringy filaments that hold it to the rock were destroyed, <<These are byssal filaments>> and a weird red growth retracted out of where the foot is! <<It had entered the byssal opening of the clam?  Troubling indeed!>> I have no idea what it could be.  I tried to flush it out of the rock, but to no avail. <<...?>> I was thinking maybe some kind of slug, flatworm, maybe even algae or blood, I've never seen anything like it, and can't find anything that resembles it on the internet. <<Hmm...>> The Clam seems fine right now, very responsive to light and stimuli, and I've had the clam for about 3 months with no problems. <<I hope you have repositioned it away from this critter>> No snails or anything on the shell.  When I checked this morning to see if the red thing was back, it was, and retracted right back into the rock! <<curious...>> Any ideas?? <<Not without a picture...or at least a better description.  But at any rate, this sounds like an organism you may want to remove from your system...for the clam's sake if nothing else.  Can you remove the rock in which this thing is hiding?>> Attached is a pic of my clam...couldn't get one with the weird red thing though :( <<A nice looking clam>> Thanks, Steve <<Regards, EricR>>

Crocea Clam Crisis?  6/20/06 Hello Sir/Ma'am, <Scott F. here today!> First of all let me say thank you for all the help that you have provided to me over the years in this hobby. <You're quite welcome! We're glad to be of service!> My tanks specifications are: Nitrate 2.5, Calcium 400-425, DKH 10.96, Specific Gravity 1.024, Temperature is kept constant at 77, no Ammonia or Nitrite. I have a 2 month old 200 gallon reef tank. My problem is that after carefully acclimating 2 Crocea clams I put them on the sand bed of my tank with two flat pieces of rock underneath them. These clams immediately opened up and have stayed that way for 1 week. Yesterday, I came to have a look at the tank and received a shock. The larger (approx 5 inches) was gaping, spewing white film (presumably from his footing). I turned him over and saw that the footing was stringy with a sort of blackish tint to it. I can only deduce (since the water quality is kept pristine) that is was some sort of internal parasite or possibly a bristle worm? <Gaping and discharge of material is almost always a sign of some sort of induced stress, most likely as a result of collection/shipping/acclimating trauma.> I immediately put a zip tie around his shell to relieve his main muscle from stressing and put him in my refugium. The clam did not survive and was pronounced dead shortly after. One bit of information is that I purchased this clam from the LFS the day that they received it. Could this be a matter of stress? I am at a loss, please provide any insight you can to my dilemma.   Thanks so much, Matthew McGhee            <Well Matthew, I'd attribute this to stress, in the absence of other obvious problems, such as a damaged byssal gland, etc. Your water parameters look pretty good. If you attempt clam keeping again, I would certainly pay very careful attention to selection, and acclimate them quite slowly. If you are serious about really good quality clams, so check out WWM friend Barry Neigut's ClamsDirect.com site. He has lots of great clams, and an amazing treasure trove of information on clam husbandry! Best of luck! Regards, Scott F.>

- Crocea Clam Lighting and Quarantine 6/16/06 - Hi Crew, I looked through the FAQs on clams and lighting, but want to get a personalized opinion in this case, as they seem to vary a bit. I have a 12 gal NanoCube DX for my quarantine tank. It's got two 24W 50/50 PC lights, and I put in a colonized sponge filter, carbon, and a poly-filter. I plan to add a 3-4in T. crocea clam as its first inhabitant, which will then be moved to my display tank. I want to make sure the lighting and filtration in the quarantine is sufficient for such a clam. <The lighting is not... but if the clam is only passing through, then it really won't matter so much.> My intent was to elevate it so to be closer to the light, since they are not terribly bright. <Or strong/intense.> My display tank is 58gal with a 400W 20k MH. Will I have to photoacclimate the clam upon moving it to the display? <It won't hurt, but clams, unlike corals can close almost completely to get a break if they need it.> Thanks for any advice! Jason
<Cheers, J -- >

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