Derasa Clam Localized Receding Mantle

[Scott23]

Hi,

I have had a Derasa clam for about 3 months. It has always appeared to be very happy. Recently I noticed that part of the mantle has receded significantly. When I try to look up information, all the cases I see involve general recession of the mantle all the way around, and not so localized as in the picture below. Any advice or recommendations would be greatly appreciated.

 

[Rainblood]

Look up pinched mantle disease

 

[Scott23]

Thanks! It looks like treatment is a freshwater dip. I will give that I try.