strange shell growth on crocea

[exoticaquatix]

i have had my crocea for about 10 months now and it seems to be doing fine, there are a few things that lead me to believe its not as happy as it could be however. for one thing the color has shifted from bright blue with a noticable pattern to a blue with a goldish sheen and no pattern except for very small dots along edge of mantle. another thing is that it expands farther than any clam i have ever seen despite strong lighting (400 watt MH placed about 18" from clam). another thing is that, as stated in the threa title, the shell seems to be growing thicker not larger. i have in the past noticed the small white snails but have been making efforts to remove them as i see them.
could these snails be the root of all these issues? he has looked this way for as long as i can remember but has always opened and been responsive. any help would be great. thanks.
-nick

 

[deepbelow]

have you tried to get the snails at night?? how old is your halide? are you using any suplementation bulbs(pc, vho, ect..)? what are your water parameters, calc alk phosphate ect...?

B

 

[jmaneyapanda]

just out of curiosity, how can you tell the thickness of the shell? I dont beleive that crocea grow very quickly, so other growth is not as obvious on some of the other clams.
Browning is usually a symptom of lighting issues. As deepbelow said, check your lighting rig to be sure all is well.

 

[mbbuna]

i see in you sig that you have 400 watt 20K bulb on a 65g tank. is the clam on the bottom of the tank?

about an hour or 2 after lights out remove the clam and brush the shell. do this every other day for 2 months. brush the shell even if you dont see any snails, this will remove any egg sacks or tiny snails. then you can slow down to once a week for another month. then just keep an eye on the clam

 

[exoticaquatix]

i have to admit im not much of a tester but when i do check up on things im usually pretty close to NSW values. i use RO/DI, feed high quality foods only as needed and do 20% monthly water changes so phosphates should not a problem.
my lighting should not be an issue as i dont use bulbs for more than 9-12 months. the clam is on a rock no more than 14 inches from my 400 watt 20k XM that has been burning for about 2 months.
also its not browning, its blue with an almost gold sheen to it. he is also very responsive and retracts and expands quickly when disturbed. its just that he started with a nice pattern and now he lacks one all toether.
the growth just seems odd to me in that his shell is growing in and not up. the new growth does not expand upwards so much as it stacks up on its self. maybe im just being paranoid about that part.
last night a checked on the snail situation a couple hours after lights out and saw both spiral and more round shaped snails on and around him. the problem is he is on a large rock that is a part of the main reef structure. can i just siphon off the snails i see at night or do i really need to scrub?

 

[mbbuna]

you really need to scrub to remove any unseen snails or egg sacks. tip the clam to one side and take a sharp knife and cut the byssal threads as far away from the clam as you can, they you dont have to take the rock out.

the color could just be normal or it still could be your lighting. regardless of watts and par, 20k replicates a deep water environment, Croceas are shallow water,reeftop clams

can you post a pic?