Need help with Dersa clam.

[lakereef]

Lost a maxima I had for almost a month yesterday and I'm worried about the dersa I've had for a month as well.


Can anyone take a look at the pictures and give advice.

Parms are in check and sps all seem fine and growing. I started GAC yesterday.

Nitrates 3ppm
Alk 8.5
Calcium 450
Lights are radions at 80% 8 hours a day. It's on the sandbed.

Appreciate any advice. Tired of trying so hard and still losing clams.

 

[JRR1285]

I think your Derasa looks fine. It even has a what looks like light colored shell near the mantle indicating growth.

I too lost a Maxima a few months ago but my Derasa made it through like nothing was wrong. I came to find out that my ALK was very inconsistent and the Maxima being much smaller seemed to not handle the swings as well as the Derasa. A week or so ago my Derasa started to retract and looked like death for a couple of days. I started supplementing 2 part in addition to the saturated lime water top off I was using. It recovered in a few days and is showing growth again.

Again, I think your clam looks good. If you can take a look at night when it is retracted and you see bright white shell edges it is healthy. Also of note, they grow really fast. Mine was under three inches last year when I got it in June. It is now pushing 6+ inches on the shell and looks huge when opened. My 40 breeder will not be a suitable tank much longer.

 

[MondoBongo]

have you lost other clams previously?

the rest of your reef looks fantastic.

i concur with JRR, that derasa looks pretty darn good. has been unresponsive to shading, gaping, or giving other cause for concern?

did you QT these guys, or have you been checking after lights out for pyramid snails? they tend to hide around the byssal opening during the day, and come out after dark to feed on the clam.

i lost a derasa a while back while in QT. it had been a new addition i had for just under 10 days. got it from LA/DA. it looked fine at first, but then quickly went down hill.

sadly with Tridacnas they tend to look fine, right up until they're not. they often don't give too specific an indication of problems until it is too late.

how was the maxima up until its demise? was it showing a good growth edge, good responsiveness? any indication of pinched mantel or other problems?

 

[lakereef]

Thanks for the reply guys.

I guess that's part of my concern is the clams look pretty good, but then bam the next day they're dead. I'm unsure how close I need to watch any small changes. The reason for concern on this one, it started to curl the mantle back over it's shell a bit as you can see in the pictures.

I inspected both pretty closely for any pryamid snails and don't see anything. The maxima maybe showed some sign of pinched mantle for a day or so before death, but since I've never really seen what that looks like in person, i'm not really sure what that means. It was clamped shut a bit more than usually before death.

I've lost clams in a tank years ago to polyclad worms, and this doesn't seem like that as the meat was still in the clam after death unlike when being eaten by the worm.

Guess I just hate losing something for an unknown reason as I don't know what to do better next time.

 

[Tigerdragon]

Clams really need stable conditions as they will suck alk and ca quite rapidly they also need good flow and light the dersa's are more durable as compared to the maximas best thing is to watch the swings and pyramid snails

 

[lakereef]

Need help with Dersa clam.

Haven't had any swings. I have 500+ gallons of water and all has been between 8-9 alk.

 

[MondoBongo]

Guess I just hate losing something for an unknown reason as I don't know what to do better next time.

i am 100% with you there. it always frustrates me beyond belief when i can't figure out what i did wrong, or what went wrong.

you don't by chance have any tank residents that might be bothering the clams, do you? pygmy angels, unhelpful blennies, or maybe a confused tang?

do you happen to run GFO? i've heard that can irritate clams sometimes.

 

[lakereef]

Need help with Dersa clam.

I do have quite a few fish but I'm quite sure it wasn't them. I was so obsessed with trying to see what was wrong I'd have the web cam up on one screen at work watching it and it just went downhill very fast over a 2 day period. Didn't ever see anybody picking on it.

Not running gfo, don't even test for phosphates anymore as I don't have any algae and sps are growing great.

 

[lakereef]

Have been running active carbon for a few days now since the maxima died and the dersa is looking better. Also raised it off the sandbed to give it more light.