whats hurting my clam??

[izzie]

Alright i got a crocea about 3 weeks ago. Hes in a 10g nano with a 10g sump. Looked great up until yesterday. He still closes when touched or a fish swims over him but he wont open like he used to. I do run phosban since i had an algae outbreak. Not sure if thats bad to do or not. He is under 150watts of lighting. Dont think thats the problem since my brain just died due to over lighting. My paremeter are as follows. Yes i probably spelled that word wrong.
Ammonia 0.0
Nitrite 0.0
Nitrate 5
PH 8.2
S.G. 1.023
Temp 80F
Calcium 380
Alk 13
light 150watts 14000k mh
clam is about 6" from surface
clam is 2.5"

I have pics and hopefully there not to big to post. The first one is my clam befor he started looking wierd and the ones to follow are of it after it is unhealthy. Also i have some bristle worms could that be a problem....oh and im not positive but there is a tiny hole in the bottem of it kinda where the bigger opening in the clam is. Im not sure i can just see light on the rock below that part so im worried it a hole and im freaking out thinking my tanks crashing. Also when i first got him i moved him and he had slightly attached to the bottem of my tank. I gently ever so gently pulled him off it and put him on a rock where he quickly attached. Dont know if that has anyhting to do with my problem but thought id make everyone aware of that.
Thanks.
Izzie
Edit: Alright i dont know how to attach a pic on this forum so heres a link to a different post with pics on a different forum.
http://www.nano-reef.com/forums/index.php?showtopic=83888&pid=764071&st=0&#entry764071

 

[NaH2O]

Welcome to Reef Frontiers!!!

How long ago did you move the clam? IMO, your specific gravity is a tad on the low side. 1.026 specific gravity equates to a salinity of 35 which is NSW levels, however, I'm not sure if this is your problem. Have you checked the clam for pyramid snails? Do you have any fish picking on it?

*moving to the clam forum for Barry's input*

 

[FishinInTheDark]

Clams can also be sensitive to salinity swings. In a ten gallon tank, they can be pretty rapid from just daily evaporation. I would suggest setting up an auto topoff, or being sure to pour water in twice a day.

Are you feeding him? Until 3" or so, they don't have enough mantle to provide enough photosynthetic energy. You'll want to get some live phytoplankton for him. In a small tank, you can run into water quality issues fast, so you should think about the "bowl method" of clam feeding.

Also, your calcium is a tad low. I'm sure that's not the problem with the clam, but you'll want to carefully begin adjusting that to around 400.

Good luck!