Injured Neon Tetra

[kanokoro]

I feel absolutely awful I was doing a water change and left the tank for one second, when I looked back there was a tetra that got sucked through the tube and into the bucket. quickly scooped him out and got him back in the tank, but then saw he sustained some sort of injury. His gills on one side look red/bloody, and there is a fleshy lump next to it.
No idea what I should do with him? salt baths to prevent infection or just leave it?

seems to be able to swim fine, but is now hiding near the back of the tank

 

[Archerfish]

Sad, but those things happen. You didn't do it on purpose. Can you isolate the fish in a hospital tank?