Hi Keri and christy, thanks for the replies and advice.
Last night, the wound area actually had a clear air bubble over it; I believed it was probably due to the wound being near the gill and the expelled air was being trapped?
Unfortunately, the fish lost its life to the powerhead this morning, most likely due to being weakened by the infection. I'm a bit disappointed since I've had it for over a year and it was even spawning eggs with its mate.
It's okay, as this hobby is about learning anyway, and I'll be sure to make things better for the next Bangaii that I buy
.