clam not opening?

[wnutz]

i got 2 clams 2 weeks ago and 1 of them isnt openening as much as the other i cann see a little bit of the mantle poking through the shell but not much i have them on the sand in a 24 inch deep tank with 150w 10 k halides is it not opening because its not getting enough light and it is the smaller of the 2 both are 2 to 21/2 inches.

 

[mbbuna]

what type of clams are they? and what fish,shrimp and crabs do you have in the tank

 

[wnutz]

its a maxima but as i said the other clam is openning and they are sitting side by side.

 

[mbbuna]

what fish, shrimp and crabs do you have

 

[The steven liu]

One thing you can try is to relocate the clam, it may not like the water flow of where it is, different clams have different preferences so just because one clam is happy doesn't necessary mean the other should be. Another thing is check for parasite if you see little white snail around the clams' mantle then you are in touble. Lastly, some clams are already under stress and in bad health when it reaches home aquaria and many will appear healthy even though it is already dying.