Friend Lost two Croceas overnight..

[Ed Hahn]

Barry,
A friend of mine recently lost two croceas overnight. He told me his water parameters are Ph 8.2. , Alk 3.5, Calcium 400, and Salinity 1.025. His tank is mostly softies, that include toad stool leather, zooanthids, etc. What are some possible reasons for this happening?
Thanks in Advance
Ed
ps. I pmed you with more information.

 

[NaH2O]

Ed - how long had the clams been in the tank? What are the other inhabitants/fish in the tank? Was he adding anything to the tank, or were there any chemistry shifts recently? I'm assuming since you said the clams were lost overnight, that they looked perfectly healthy the day before?

 

[Barry N.]

Ed,

Received your PM and wrote to you and I see that Nikki asked you some of the same questions.

 

[Ed Hahn]

Barry,
here is what I was told are his tank paremters.

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Post from friend..
pH 8.2 Alk 3.5 meg/l, calcium 400, temp 78.7, s/g 1.25. everything else in the tank is fine. It happened so quick, I'm wondering if it was a bristleworm or something along those lines. everything I can check is ok. this is the problem with a small tank, the smallest contaminent can just cause fits. But everything else in the tank is fine. thats why its so puzzlin

Barry and Nikki,
The clams have been in this tank since first week end of August 2005.
Ed

 

[Ed Hahn]

My question first question is ..Could a undetected temperature swing kill a clam overnight?

 

[Barry N.]

Could a undetected temperature swing kill a clam overnight

In a few hours, don;t think so but then it would depend on how high or low it got but if all the other livestock is ok, I would have to say no.

What size tank?

 

[Ed Hahn]

I believe its a 40 gallon tank. It is extremely clean. Could they starve and fall apart at same time?

 

[NaH2O]

How large of clams were they? I'm guessing if they were crocea's that they had sufficient mantle size for food (I haven't really seen a tiny crocea...doesn't mean they aren't out there). Was his lighting ok? Then again, that would be a slow deterioration, wouldn't it Barry?

 

[Ed Hahn]

I am totally baffled on this one. If his water parameters are as stated, what else could have possibly happened? He does have a coral beauty and Red Hawk fish. Other than that, I remember hermit crabs and snails. I am still reaching here.
Thanks in Advance,
Ed

 

[Barry N.]

that would be a slow deterioration, wouldn't it Barry?

Yes

He does have a coral beauty and Red Hawk fish.

CB are hit and miss but not sure about the Hawk Fish. How long had it had the clams?

 

[Ed Hahn]

Nikki and Barry,
He has had the clams since first week end in August 2005. I think they both were 3 inches in size. He is running a 175 watt MH on a 40 gallon corner tank . Is it possible for a Coral Beauty to eat both clams over night?

 

[Ed Hahn]

one more thing, I just heard. He has a yellow coris wrasse, and emerald crabs in the tank. I just heard that, sorry for late reply.
Ed

 

[richard55]

OK I have a couple of questions, one did he did the clams when he bought them. There are several parasites that may have come with them that could kill them. Has he added any new rock, there are several hitch hicker crabs that love clam. Also I see zero mention of lighting and flow. The reason I ask is without good lighting they will die. Maybe not over night, but still something to ask about. Also has the water been tested for copper.

 

[Barbie]

He mentioned lighting, they were under a 175 watt halide. I can't see lack of flow killing two overnight if they'd been doing fine, IMO. That's almost got to be some big spike in ammonia or a pH crash. The Coral Beauty would have started nipping the clams, which in turns make them close up and act stressed. I also don't think that would kill 2 overnight. I'm not helping actually figure out what the problem could be though. Sorry about that Ed!

Barbie

 

[Ed Hahn]

Thank you Barry for Pm. I am sorry for late reply on it. I am still working 13's at work. I will run it by my friend. As always your are right on the money. How does the size of a aquarium effect the stability of a clam?

 

[Barry N.]

How does the size of a aquarium effect the stability of a clam

The smallier the aquarium, the more you might experience chemitry swings due to evaporatiion such as pH, salinity. The more water volume to less chance of messurable swings. IMHO.

 

[Ed Hahn]

How fast can bristle worms over take a clam or two?

 

[chris&barb]

bristle worms wont attack a healthy clam, they got a bad reputation because they are the first on the scene when a clam is dieing and people think that they are the cause

 

[ldrhawke]

My money is on the yellow coris wrasse. I have a clown wrasse that is still small but he would tear up a clam very quickly if given a chance. He flips over pieces of coral ten times his weight looking for worms and pods all the time. All wrasse can be agressive and eat snails and crabs. He may have discovered the clam was a tastey treat and started nipping at the clams and killing them. :evil:

 

[ragman]

Hello All,

Just joined the forum and I am Ed's friend that lost the two clams overnight. Thank you first to Ed for bringing my situation to this arena.

First, to answer some reoccuring questions, as stated by Ed the paramaters were all good. ph, alk, sal, temp etc. I had no spikes of ph, temp, nitrates, ammonia, etc, these were the first things I tested for. So we can eliminate water quality from the equation.

Second, The lighting is a single 175w 10k MH with a single 18" reg. flourecent actinic bulb to supplement. Don't know how much this actually helps, but it adds a touch of blue to the look. The depth of the tank is about 18" deep, and the clams were on the bottom of the tank.

Third, with such a small tank, water movement is a challange. I have 5 powerheads within the tank, 3 of them being oscillating types at various levels within the tank. the other two are stationary type. One of the oscillating powerheads was at the bottem level, and for the most part swept back and forth over the top of the clams.

Fourth, the clams were in the tank for 3 months and were open with the mantles spread wide all the time. They were roughly 3-4" in size. At no time before the loss was there any indication of stress.

No other corals show any kind of sign of stress. I lost nothing else, everything else is fine. The fish in the tank were never observed nipping at the mantles, but obviously I can't watch them 24/7 but I highly doubt that it was a fish.

With all of this taken into account, I have to believe that it had to be a preditor, because of the quickness and the fact that it only affected the clams. I am in the mist of setting up a new 200 with plans to inlclude numerous clams( my wife and I think they are the best looking thing in a tank). If anyone has any suggestions other than the conclutions that I have come to, they would be greatly appreciated. Thanks in advance.

John