Derasa Clam not fully opening

[cap11885]

so i noticed my Derasa Clam hasent opened fully in the last 2 days. and it appears to be getting a little darker in color. it is in the sand of my 125 under t5 in a low flow area. i will post a pic shortly. any ideas its usually fully open and a healthy light brown color. not its barely open and a draker looking color. there are no snails on or around him. and all i keep are turbo and Nassarius. it still reacts to light.

[cap11885]

this is the clam currently
183779

183780

[cap11885]

this is how it normaly looks
183781

[cap11885]

also one of my cleaner shrimp seams to be attracted to it lately

[cap11885]

any ideas???

[moliken]

he does not look good. how do you check for snails, as that is my first opinion? if you are positive, no pyram snails, i'd suggest a properly done fwd.

[cap11885]

i dont have any pyram snails. i have looked the clam over both in my hands and in the tank. i hear many ppl say never dip you will kill it then ppl say dip. idk what to do or how to properly dip a clam.

[moliken]

when did you check the clam for snails? google fresh water dip for clams.
fwd is a last resort, but yr clam looks like it's there

[dunk373]

i have the same deal as you my clam is open but the mantle isn't extended past the edge of the shell. The weird part is at night is opens less wide but the mantle extends out. I have bad clam luck and personally am done with them. I think they need nitrates to survive. I have no nitrates.