Fire Shrimp Sick

[RandomQubit]

I have a fire shrimp that I got about two weeks ago and noticed he has a black spot on his tail after molting.

I had a larger clown that was beating on him and I put her in a breeder box and eventually took her back to the store because she was nipping at everyone including me. Can’t tell if the clownfish damaged the shrimp or it has a disease.

 

[RandomQubit]

I also have an emerald crab that appears to be just fine as well as a few snails.