Clam advise

[Myka]

Originally Posted by bignose

Sorry Myka I must have missed your message while I was typing another.

The tank is 18" deep, light fixture is 4" from the water and the Clam is 4" from the water surface(moved from 8" yesterday).

Ammonia, Nitrates, Nitrites: 0
pH: 7.8
KH: 90
Ca: 480
Sal: 1.027 (making RO water right now)
Temp: 80F

I don't have the Kent bottle with the clam on it anymore but I beleive it was phytoplex.

Your calcium and alkalinity is out of balance. Your alkalinity at 90 ppm is equivalent of 5 dKH. Proper ratios are:

1.4 dKH to 350 ppm
2.1 dKH to 375 ppm
5.6 dKH to 400 ppm
9.1 dKH to 425 ppm
12.6 dKH to 450 ppm
16.1 dKH to 475 ppm

The ratios need to be balanced for optimal absorbtion by corals, clams, and other life. Natural seawater contains 410 ppm calcium, and 7 dKH alkalinity. To convert dKH to ppm multiply it by 17.9. Keeping your alkalinity higher than it is now, and keeping it steady will also help to increase and stabilize your pH, which is on the low side for sure. It would be good to use an alkalinity buffer with pH buffering capacity like SeaChem Reef Buffer 8.3 in your case.

Although I doubt this out of balance is the cause of the clam's loss of color since you haven't had the clam in these conditions for very long, it may present an issue down the road if it is kept up like this.