dying clams


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hey quick ques...

found my clam today with its mouth wide open (more then usual).its not opening up to the top of it mantle more and more everyday ..anyone had thier clam do this?? is this a sign that its dying???? all my tank parameters are fine...
How big is your clam? Are you feeding it? What kind of lighting to do you have? Tell us some more about your sytem....
its a derasa clam. 4 inches in length.. the tank its in ( 90 gallon corner) has a 20k 250 metal halide on it with vho actinics. it seems as though it doesnt want to come out of its shell.. feed it kent marine phytoplex and dose the tank with cyclop eeze every 3-4 days...all other corals seem fine.... the only thing i can think of is the boom of snails i've had...multiplying like crazy (no fish or other livestock in tank). anyone know if they can annoy clams>>?
Have you checked for pyramid snails? Get a flashlight at night and check to see if these pesky snails are bothering the clam. During the day the'll be harded to spot but usually hang out near the base or up within the shell. It's easier to spot them at night...
yes check for those snails, best thing to do is if you can pick it up and see if they are under it on the bysal foot. If there is pick as many off as you can and use a new tooth brush and scrub the shell really well. Also if you can get a pic, that will help.
Look for boring holes on the clams as well. You might have a worm attacking it as well.

From your initial description, I'm a bit confused. When you say "it's mouth wide open" do you mean the inhalant siphon? Is the behavior that the whole clam is mostly staying shut or that it's gaping?

its exhalent hole...near the bottom gradually got bigger and bigger...it started to peel off the inside of its shell.. found it today morning dead...quickly removed it...no signs of snails or worms...had it for over a year.
Sorry about your loss Slayer77. I do know that clams are very susceptable to changes in ph, salinity and temp. Did any of these change?

That condition is what is called "gaping". Can be caused by many different stressers. It is usually the last step before the clam dies. Becfore adding any more clams, try to determine the cause- as mentioned earlier by many. Check for small rice sized snails around the clam, water parameter issues, etc.
I have 9 clams in my tank. Maximas, derasa's, Crocea's, Squamosa's.etc.

Anyway, I had a 6" Derasa bite it 2 days ago. No reason what so ever. The mantle withdrew into the clam and the thing started bulging for a better term. Left it for 2 days or so. The mantle never came out so I got rid of it before it croaked.

anyway, clams die..that's all I can say.

One thing is that I do not skim my tank. Do you? With 9 clams, I need the nitrates for the clams. They need the microsopic stuff that skimming removes.

Also just doscovered that my CA was only 200. I sure that did not help with the clam death as well.

What was your CA at?
Washowi- I think not skimming is a BIG MISTAKE. Clams do not pull as much nutrient out of the water as people think. They will utilize some organics, but not significantly more than other corals. Excess nutrient in the water will cause other major issues, as we all know, but will also stress the animals if allowed too high. Personally, I would not ever run a marine tank without a skimmer. I know it has been done with success, but I think this is dodging bullets.

Calcium of 200 is rather miserable, too. If you are going to keep clams, especially 9 of them, you HAVE to provide adequate calcium and alkalinity. Otherwise, you are neglecting these animals. They should a calcium near 400. These animals don't simply die. Waikiki aquarium has one that is like 15 or 20 years old or something. Proper care is necessary.
calcium 370,, i do use a skimmer,,,and have macroalgae... i didnt see any kinds of snail when i removed the clam..all the other coral seem just fine.. however i did add a xenia frag the day before i saw the "gaping" maybe a hitch hiker, maybe warfare,, although they were on opposite sides of the tank....i guess it will remain a wonder??
Tony...I am just going to let the comments ride. Everyone has their opinions.

But anyone who knows or has seen my tanks knows that they are in great shape and been in action for 3 years now.

I have had only one clam die in that time frame. Nuff said there. Also, no **** 200 is miserable. thats why it most likely died. It has been corrected.

It's taking all I have to leave at this...:)

BTW - Panda, who are you? have we met?
washowi wrote: But anyone who knows or has seen my tanks knows that they are in great shape and been in action for 3 years now.


I was skeptical when I found out how he was running it too but his tank is nicer than either of mine... so I cant really say a whole lot.:cheers:
Washowi- I dont believe we have met. And I apologize if I sounded abrupt in my post. It was not my intention to antagonize. So, if you did feel I offended you, again, I apologize. I know that is not the purpose or mission of this forum.

I reacted the way I did to my (inappropriate) speculation as to your intentions. When I read your post, it seemed to me as if you were promoting not running skimmers, and low calcium. I can understand that this was not your intention or action.

I also must say, though, that I liken your comment of letting the calcium to 200 with clams to someone saying, "I bought this fish, and it died because I didn't feed it". That type of comment will get some frowns, Im sure you agree. I personally have a strong issue with clams, especially regarding their care (or lack thereof by many). I still stand by my point that clams do not need "excess" nutrients accomplished by not skimming. I also stand by my point that clams do not just die. There is a reason, and unfortunately 99% of the tuime, it is owner negligence in not researching and caring for their animals. I dont find that acceptable, and I'm sure most would agree (including yourself).

Please understand, I am not bashing you or your system. I have never seen it, but I believe you and others that it is what you claim. That being said, I still think the points brought up in my previous posts still do bear true.

Let me know what you think.
No problem...everyone runs tanks different.

I will however refer you to a book called "Reef Invertabrates" by our friends Calfo and Fenner. Page 240. If you do not have the book, I will quote it as written.

And I quote" In Aquariums that are aggressively filtered and skimmed, nitrate levels can be so low that endosymbiotic zooxanthellae in clams and corals begin to suffer, with waning color of the host as testimony to it."</em>

There is alot more to read about it like bottled greenwater and other foods, but I would like to point out that alot of people have come to me to see why my clams live and thiers do not. I agree with the above statement. People tend to skim the water sooo much that the needed nutrients are removed.

Seawater is not exactly clean, so I believe ours should be as well. Not polluted mind you, but I not cyrstal clean either.

I feed my tanks like 4 times a day. As I precaution, I took water samples to my LFS. Had it tested.

Alk was 5+, Ca was 200!! (remember I was low), Nitrates were almost zero, Ph was 8.2, Phospherous was there but based on the feeding I do not that bad...

So even though I do not skim, my tank levels are the same as yours. (not the CA!!) but that is fixed and running 430 this AM.

I attribute it to the clams and corals in my tank cleaning up the water.

Maybe, maybe not. But it works and I am not changing. So yes I am an advocate of not skimming..and would tell anyone the same.

Just my thoughts, but I want to impress upon all, and anyone who knows me. My Fish and corals come just after my family in importance. Everyone is healthy and thriving in my tanks.

I have seen a couple tanks ran without skimmers, a skimmer isnt exactly needed, its just there to keep it extra clean. I didnt run a skimmer granted it was only ran without one for about 8 months my levels were great nitrates under 10.