Lost a large clam (muscle)... Ideas?

[Splach]

Hey all,

I have a good sized tank with about 300lbs of Tampa bay live rock. I have somewhere between 15 and 25 golf ball to baseball sized clams (all of which came with the rock). In the past week or so shells have been coming up empty. First it was a small (1/2") empty shell with no lid on the rock. Next it was a emptied shell sitting on the sand (top and bottom still attached but nothing inside). This morning it was a large muscle on the sand. Must be 3" across. Looks like it was eaten and then just dropped right off the rock. The shells appear intact, but the inside of the shell looks pressure washed. Any ideas?

Thanks

[freakyreef]

Start watching the tank at night with a red light. Odds are good you will quickly find the culprit.
How long have you had the rock? Sounds like its doing the munching right out in the open at night.

[Ruu]

How long have you had the clams for? I just got a shipment of TBS rock, and I have one that is slightly larger than a golf ball. I've heard that their survival rate isnt too good (I'm feeding DTs at the moment, and I'm hoping for the best) - Im a bit concerned since my tank isnt quite as large as yours and the death of something that big could be a problem.

Dave

[Putawaywet]

How long has your tank been up and running? Those are more than likely non-photosynthetic bivalves you've got there and my guess is your tank is not able to provide sufficient food to sustain them.

My suggestion is to try and obtain some quality phyto and start dripping it into the tank on a regular basis.

Brett

[Splach]

Sorry, I should have given you more preamble. The tank has been up for 11 months with the rock in. To date I have had no clam deaths. I feed DTs but typically only once or twice a week. There are a bunch of sand dwellers that are constantly spewing and sending micro-crud into the water which is why I think they have done well. The only new additions to the tank in the past month are:

1 Fox Faced butterfly (who sleeps at night)
Several coral frags and 3 large corals. I looked over the corals for any hitchhikers and there did not appear to be any (well 2 of the large corals had those little crabs that live inside the corals and never move.

Thanks