Trouble with my new Gigas.

[virginiadiver69]

I have had him in the tank less than 24 hrs. I have noticed the top edge of the mantle starting to rot away. It is about an inch long and 1/4" wide. Otherwise he looks healthy, responds to shadows. My param are, sg=1.025, temp=78, Ammonia/Nitrite/Nitrate=0, Calcium=420, dkh=9.6
I also added a squamosa at the same time and he is fine.

 

[mbbuna]

can you post a clear photo of the clam

 

[prugs]

Could just be damage from shipping/transport.