Freshwater clams

[Mocoon]

Hello.

I have come across a unusual issue with one of my tanks. I had/have a tank that's been going a year strong with live plants,cardinal tetras,silvertip tetras, and cherry shrimp. The tank is fully cycled, and parameters are of pristine water conditions. (All my levels are perfect)

I added 1 freshwater clam to the mix about 3 weeks ago. Since then my tank has gone from fish paradise to nightmare tank scenario.

All of my tetras have neon tetra disease, and all my short leaf sword have been slowly dieing. Other then adding my 1 freshwater clam, i have not changed a thing with how i run my tank. Is it possible for freshwater clams to hold neon tetra disease, and what could they possibly be doing to make my sword all die?

The clam was still alive as well and seemed to be loving its new surroundings as it felt the power of bringing death upon its fellow tank mates.