[leebca]

Information is coming in bits and pieces. Wish I had more info and better photos.

The Coral Banded Shrimp, though very attractive is a predator and has been known to attack fishes. It can be very possessive about its territory, too. Not a good invert choice for a community fish tank, I'm afraid.

Some observations:
Your alkalinity is not balanced with the calcium. Wonder what the magnesium concentration is like?

I have no idea of the tank size, equipment, foods, nor other inhabitants. Was the fish quarantined before putting into the display tank?

The only answer at this point:
Antibiotics made for marine fishes, in a QT will do no harm to the fish if applied properly.

This is a common symptom of brooklynellosis.