Derasa Clam Problem/Questions

[IFbettas]

Yesterday I finally got a derasa clam for my 180 gallon sps reef. He is about 2 inches long. The thing is he is barely opening up at all, like a little more than half an inch. Whenever I have gotten other clams they opened up fully right away, and attached to the substrate. I put him on a clam shell on the bottom of my reef for him to attach, but he hasn't yet. Just wondering how long it takes for derasas to open up and attach to the substrate (keep in mind this is a small one). Thanks

 

[stlrams88]

Took mine a few days to attatch, and a few days to fully open up.

 

[rendogg]

It could be a number of things, I'm assuming it was healthy when you got it. It could be too much current, too much light, damage during removal, water parameters changed too drastically or need to be adjusted, something (fish,worm,crustacean,etc.) is irritating it, etc. Start with the simple ones and do it by process of elimination.

 

[IFbettas]

The area where the clam is doesn't get very strong flow, and that is where I keep my lower flow corals like acans. My water parameters are excellent, and it is an sps reef, so I always need perfect water quality. No fish or inverts have been bothering it that I have seen, and I don't have any fish/inverts known to bother these. I checked for pyram snails when I was acclimating it and there were not any. Any other ideas?

 

[rendogg]

It can be tricky sometimes. It might just be adjusting to your conditions vs. the conditions it came from.
Just recently my clams started closing up on me, I couldn't explain why, they had been happy and comfortable for almost a year. It got to the point where the mantles were completely withdrawn and I could see a rim of shell....not good! I had checked my parameters and they were all fine and I watched my tank to see if anyone was pestering it and saw nothing....I couldn't explain it! I decide to move all of my clams into my other tank plumbed into the same sump....within days the mantles were out and regaining lost colour. I figured it was something disturbing them....my fish only seem interested in me when I'm in front of the glass, who knows what goes on when I'm not around?!

 

[IFbettas]

I was just reading in my book Giant Clams in the Sea and the Aquarium, and Fatherree said that derasas have the most diverse mantle extension. Sometimes the mantle only barely covers the edge of the shell (which is what mine is doing) and other times it has huge fleshy mantles like croceas. Mine is still not opening up as much as he should though. I noticed that he was spewing out a little zooxanthellae a while ago. I have a couple croceas that are doing fine, so I'm pretty positive that nothing in my tank bothers clams. I'm hoping this little guy will grow into a center piece for my reef.