Clams closing intermittently

[ldm1062]

Has anyone had problems with their clams closing off and on during the light cycle, I have croceas,maximas,and squamosas and 1 derasa I have 6 t5 lights and 2/250 MH 20k clams are at varying heights none are on bottom my tank is 30" deep the derasa is the only one that seems to stay open all day

 

[cheeks69]

closing off and on during the light cycle

How long have they been in the tank ? If they're new additions did you acclimate them to the new lights ? What is your current fish list ? Mine are open all day and only close slightly when fish get too close.

 

[CATALYST]

Mine will close if something disturbs the water flow or the light. Make sure there aren't any BAD snails bothering it. I found some wacky predators in my tank.