So as of about 2 weeks ago i noticed my clams mantel was contracting on the back end. so i started adding calcium to see if that would fix it. it helped a little but still wasnt back to normal. so i did what i was also advised and put him in fresh water for approx 8 minutes then put him back into my tank. did that he closed up and wouldnt open for about 30 minutes but then again still wouldnt open all the way up. once i put him back into my tank after the fresh water dip he rolled himself off the top of the rock onto the lower part of my tank so i was worried because he had not tried to move in the month he was on top of the rock. i figured it was because i put a new led set up on my tank and he didnt like it so i put him on the sand bed he flipped himself on his side and sat there for awhile. i finally moved him back up to a rock and turned down my lights. i am worried because he doesnt react to my hand over the light as quickly as before could be be dieing? is there something wrong with him? i was told by a frag seller that clams dont like led lights and they will die truth or bull? please help!