Derasa shell seperating???


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I have a 5" Derasa clam, I've had it for a year now, it was 4" when I got it, and I noticed last night and today that it was laying on it's side . I went to stand it up, I used a long rod to gently nudge it with, and I noticed that it seems as if the 2 sides of the shell moved sepreately from each other, almost as if they were no longer attached to each other or as if the "connector" between them was weak. I did notice the other day that it seemed to have released some filaments that were attached to some sand, there wasn't much there. It has never been attached to any LR and has always been on the SB.

It's on the SB and I haven't seen any snails or any other creatures around it or bothering it. The water params are all in check, Trites, trates, ammonia and Phos all 0, salinity 1.025, PH 8.3, calcium 350-400 (I drip kalk daily), Alk 9.5-10 DKH... It's mantle is extending out full and other than the problem with the shell, it seems to be very healthy. It extended outit's mantle within minutes after I stood itup. About 4 days ago I moved it to remove a piece of Xenia, that had released itself from it's perch on the LR, and that's when I noticed the small piece of filaments from the clam. The 2 halves of the shell seemed to be fine at that time and the clam closed up tight. Today is the first time I've noticed any problems with the clam. Of course I don't make it a habit of moving things around in my tank. I only decided to stand the clam up because this was the first time I have ever seen it laying on it's side. Everything else in the tank seems to be fine and healthy, corals, fish and LT anenome. Has the loss of the filaments weakened the shell where it's joined? Will it strengthen back up? I just would hate to loose the clam. I also have a Squamosa clam, they are about 2"-3" apart and it's fine. Thanks for any help and advise.
Do you have a picture? Loss of adductor control is a bad sign. Can you see thru the incurrent siphon? The gills should be visible as well as the adductor muscle behind it. Unfortunately the mantle may stay expanded despite the clam dying. If this is the case you'll know soon. I hope this is not the situation. Adam
I just got home from work. I had to stand it back up, it was on it's side again, but I got some pics, it opened right back up as soon as I repositioned it. It also worked the muscles, kinda like it was trying toget comfortable... LOL
Hope these pics help.
last one... Again, when I stood it up, it was like the 2 halves of the shell moved independently of each other. What causes the loss of the adductor muscle and is there some way to correct it or can it grow back?
From those shots the anatomy looks OK. Can you take a more panoramic view of the clam and one of it's byssus from the bottom? Adam
It sounds to me like the actual hinge is damaged, not the adductor muscle. I have heard of this before, but have never had it happen. IIRC it will heal/grow back as long as the two shells stay aligned correctly.

The hinge is the brownish tissue on the bottom of the clam, where the two shells are actually joined. Can you take a picture of the bottom of the clam?

Good luck,
Here is a more panoramic view of the clam. I would rather not move it around to take a pic of the bottom. But yesterday before I stood it up, I could see the bottom and the "hinge" is not there as best as I could tell. Once the lights come on I will get a better pic. This pic was taken last night with only 2 actinics and 2 50/50 lights (each one is 65W PC) on. I have 2 250W MH also, they come on during the day, that were added 2 weeks ago when I upgraded from 520W PC, to 500W MH and 260W PC (I removed 1/2 of the PC lighting and added the MH). They are currently on for 7 hours per day, which I'm slowly increasing to give everything time to acclimate to the new lights.
I took 2 pieces of LR, long branches, and laid them down with the clam between them to support it. So far it seems to be doing fine except for the "hinge" that is missing. Here are 2 new pics I took tonight.
Here's the second pic. The clam is respondiong normally to shadows and such. Will the "hinge" repair itself or grow back?
It should repair itself provided the hinges stay aligned correctly. I don't know how long it will take, however. I'm also not sure if it will be as strong as the original hinge or not.

Keep us updated on his progress.