The joys of keeping Jars! 
The wound although looking bad is probably only superficial as it's only a flesh wound.
Very strange wound mind to sustain from its surroundings as it's difficult to swim into something side on, could be some skin damge & then possibley an infection has set in - unless it apeared over night?
I'd dose the tank myself with a broad spectrum based Fungus / Bacterial remedy just to stop any secondary infections.
A small dose of equilibrium salt may also be beneficial.
The wound although looking bad is probably only superficial as it's only a flesh wound.
Very strange wound mind to sustain from its surroundings as it's difficult to swim into something side on, could be some skin damge & then possibley an infection has set in - unless it apeared over night?
I'd dose the tank myself with a broad spectrum based Fungus / Bacterial remedy just to stop any secondary infections.
A small dose of equilibrium salt may also be beneficial.
