Sick Maxima question?

[shez15]

I'm new to clams so bear with me! I purchased a blue max about a month ago from my LFS. It was healthy in their tanks and mine. Three days ago I came home to find the clam was completely turned around and facing a diff direction. My girlfried said she saw it rapidly opening and closing earlier that day. Today, he doesn't look so good. The mantle in the middle is looking white. Although the mantle will retract, the shell will not close. Any ideas as to what may have happened???? My anenome, corals and other two maximas that I bought three weeks ago appear fine.


A little about my tank:
55gal reef w/60 lbs of lr
skimmer
(4) 95W VHO's
Undetectable nitrate and nitrite
Ran out of Ph and alk test kits, so don't know but always has bn stable in the past

 

[Peabody]

First, your lighting may not be sufficient for a maxima, this would seem to be confirmed by the central bleaching you describe. Central bleaching is where the clam expels it's zooxanthalle (bad!) due to lack of light. Second, central bleaching can also be caused or furthered due to lack of nitrate. Clams need nitrate!

In most cases Maximas need metal halide lighting (and small amounts of nitrate) for long term health and success. 250watt halides are needed for a maxima's needs in your size tank. VHOs can't penetrate enough PAR to satisfy your clams like a halide can. Once in a while, someone will have success with a clam under VHO, but that seems to be the exception and not the standard. How close to the lights are your clams?

You need to be monitoring your PH, calcium, and alk regularly. THey might have been stable in the past, but they can chage quickly and drastically if something is wrong.

Lastly, how big is the clam, and are you feeding live phyto. He could be starving if he's small enough and not getting live phyto.

Best of luck,
Jeff