The clams that I currently have are 2 croceas and 1 derasa. As of now, I have the two croceas on the top rocks they are both attached fine. The first one I put in there attached to a smaller rock I had put it on, however the most recent clam, my second crocea did not attach to the smaller rock quite as well. I placed it in a nice crevice of my larger rocks, and it seems to be happy in its place. so, both the croceas are near the top under the spotlight of my evil par38's 20k with 40 degree optics. the third clam i have is a derasa and it is sitting in between two smaller rocks on my sandbed. they all seem happy and open and close everyday with no issues. they are also very sensitive to when my hand covers the light for a second which i am told is a sign of good health.
here is an earlier photo of my crocea about 2 weeks after i got it. the second crocea that i got is sitting where the hammer is in this photo now.
this is the newest clam, sorry about the crappy photo its with my iphone. am i correct in thinking this is a crocea? i really hope so, otherwise im going to feel quite stupid...
here is my derasa although from the time this photo was taken, it has made a 90 degree turn although is still sitting in between those rocks. i am a little worried it might be attached to the bottom glass which would make moving it a real pain. This clam has also opened up much more since taking the photo.
I don't plan on getting anymore, although I would love to. I've been monitoring my caclium very closely after I get each one to see if anything changes, but nothing yet.