Derasa Closed Slightly

abcat1993

New member
I just got a derasa and a crocea two weeks ago. The crocea appears to be fine (I think):
042.jpg


The derasa also looked like it was doing well for the first few days:
NewPictures202.jpg


Since then the derasa has been closed up partially the entire day (sorry, forgot to clean the glass):
043.jpg


There are snails that I've had for over 9 months now which look very similar to pyramidellid snails, however I assumed that they were rissoid snails because they ate algae and didn't eat clams (because I had none). I have found some on the clams (mostly crocea though; about 20x more), although there are quite a few so they may have just been eating algae on them.

What other problems could be causing that to happen?

Lights: 4x 24" T-5 driven with icecap 660, cooled, w/ refectors over 20 gallon long
Alk: ~8
Ph: ~8.2
Ca: ~420
Po4: no test, assumed to be zero b/c almost no algae and acroporids growing(could certainly be wrong though)
Nitrate/Nitrate: Too low for my test kit

EDIT: Would like to add that there are a fair amount of air bubbles in the aquarium (although, again, the other clam doesn't seem to mind)
 
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can you post a couple pics from above please?

what bulbs are you running?

list your fish / inverts please.

how do you maintain Ca and Alk??

what and how do you dose??

did you check the clams or QT before adding to the tank?

pyramids can eat other mollusks, have you looked at what they are doing at night?? ( a few hours after lights out )
 
The pics from above will have to be without the light from the canopy; would you prefer a shot out of the water or not?

No fish, a dozen hermit crabs, stomatella snails, a nemertean, a random crab (about 1" long, red, hairy) that I just noticed last week, the snails I talked about (may be more than one species), bristle worms, copepods, amphipods, chitons (which I found on the shell of the derasa), may think of more...

I dose 2 part every morning (sometimes at night)

Unfortunately I did not check the clams very thoroughly before adding them (although they appeared healthy at the store; didn't see any snails on them, opened fully)

Now at night I find them on the clams (mostly the crocea though), and before I added the clams they would crawl around the glass, rocks and sand and appeared to eat algae. I would see a few during the day, too.
 
watch what the snails do after the lights go out, even remove the clam and see if they are up under the mantle or not. if they are you need to start removing them on a daily basis until eradicated. look for egg sacks too.

don't take the clam out of water for a pick, just shut off the flow and take a pic from above. try not to spook the clam, so his mantle is extended.
 
Alright, thanks

I have been looking at the clam after lights out and I found that they are usually close to the mantle (although I've found them everywhere). Would they be on the inside of the shell on the derasa? I've only seen a few on the outside
 
it's possible you have rissoids and pyramids. if they're pyramids they will be up at the top of the shell eating the mantle in the dark. croceas were notorious for carrying these pest a while ago, haven't heard as much about them lately.

good luck
 
try leaving the lights on, turning all flow off and holding you camera lense as close as you can to the water surface, bracing your hands on the side of the tank.

they look fine for nighttime
.
 
There's no possible way for me to leave the lights on and take a picture.... I do have a 6500k bulb that I will try shining at them and waiting until they open
 
I decided not to bother my clam too much by moving it to pick off snails, and it opened up to a normal state. Then I noticed that you could see the sand through the incurrent siphon (i.e. there was a hole in the bottom of the clam). I assumed this is where the byssal gland was, and thought that it may be damaged (beyond repair?).
 
<a href=showthread.php?s=&postid=14412423#post14412423 target=_blank>Originally posted</a> by abcat1993
Then I noticed that you could see the sand through the incurrent siphon

this is normal

<a href=showthread.php?s=&postid=14413990#post14413990 target=_blank>Originally posted</a> by abcat1993
nevermind it died

sorry to hear, you better keep an eye on the crocea. if they are pyramids, he will be next.
 
So is the crocea doomed? Is there any way to kill all of the pyramidellids, or at least prolong the clams life for a while?
 
<a href=showthread.php?s=&postid=14422604#post14422604 target=_blank>Originally posted</a> by a4twenty
if they are pyramids then you have to manually remove the pests on a daily basis, no other option.

oh, fun....

I'm still concerned that it was something other than pyramid snails that killed the derasa because I didn't see many on it... maybe they were just too far into the inside of the shell? If it was something else, the crocea doesn't appear to have it... but then again I've had things die randomly...

thanks
 
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