Earlier this week, I noticed my dojo loach floating at the top of the tank. He had a green bump on his side. I had purchased antibiotics, but it seemed too late as I found him at the bottom of the tank the next day. When I picked up him with the net, I noticed an open wound on the bottom of him. I was hesitant to toss him, although I thought he was dead, so I kept him in the net near the top of the tank. Now, 2 days later, he suddenly jerked strongly as he usually did when scared. The green bump now has a purple appearance resembling a bruise.
So, is my loach clinging to life or were those his death throes I witnessed?
Also, is/was his illness due to bacterial infection and/or parasites? Any help would be appreciated.