Need clam help

Engloid · May 24, 2011

I have a clam that came on some live rock I bought. It's not a pretty type of clam that you'd buy at a LFS. It's just one of the ugly ones that rarely have any flesh that even comes out of the shell, it just opens up a little bit to allow water to pass through.

This clam opens with its opening towards the rock, so the hinge side is away from the rock. When you touch it, it pulls itself shut and tight against the rock.

Now, the problem...
The other day, I noticed something that I thought had grown on a rock very quickly, and didn't know what it was. It was very hard, which surprised me, cause calcification doesn't happen in a couple days. As it turns out, it was where this clam was. When looking into the end of it, it's got a ton of little fins in it. It's like looking at the underside of a mushroom, but it's more oblong. I guess it's some sort of hard deposit that it built onto the rock so it could hold on. The clam is now laying in the sand, and the open side has a gap about 3/16" and about 1" long, where I assume that the foot came out so it could close tightly but still have the foot out.

Is this hard thing a part that it needs to live?
Has the clam died? It is still closed tightly.
Is it maybe trying to let go and find a better place?
Should I try to prop it on some rock where there's more water flow?

skinz78 · May 24, 2011

If the clam is closed up tight it is still alive.

Can you post pic's of the clam and the thing that is still on the rock?

dmorazan · Jun 17, 2011

i will let the clam go where it wants to go and keep an eye on it

Engloid · Jun 17, 2011

I think he's still alive. Oddly, I put him on a rock, but my wrasse knocked him off into the sand. He slowly migrated over to a rock, just on the sand, and seems to have made it a home.
I just got another clam the other day, dunno the type, but it's more the type that you specifically buy (not a hitch hiker). It came off its rock and had just a large fleshy foot....which is unlike the one that was a hitch hiker. When it came off the rock, it left a hard skeleton type of thing behind. Perhaps it grows the hard piece, attaching it to the rock, in order to have a more secure attachment. I suspect that it just wasn't happy there and pulled flesh from the skeleton piece, and will grow it back on its new rock.