I should state up front I'm newish to the hobby. Started 3 months ago. Just looking for some help.
So 10 days ago, my Blue Paradise Gourami died. From what I've been reading I think it was a bacterial infection, but I'm not 100% sure. The Gourami and my Buenos Aires Tetra had gotten into a fight two weeks prior. The tetra's nose was visibly damaged and the left side of the Gourami had multiple wounds that matched up in size to the tetra's nose. The tetra was doing fine and the gourami seemed ok, but the wounds were not healing. They actually seemed to be getting worse. On 04/12, I had to move apartments. All fish survived the move, but in the days leading up to 04/20 the gourami's wounds got more red and her belly/abdomen grew considerably in size(inflammation?). On 04/20, the gourami died. All the other fish looked fine. The tetra's nose never really got better. It was a whitish color rather than silver like the rest of his body. Fast forward to 04/27, I wake up to my leopard cory with one eye bulging out of his head and swimming very erratically...resting on plants he never got near in the past. A couple hours later, he died. Then, this morning I woke up fed the fish, dosed my usual one thread of excel. When I got out of the shower, the Buenos Aires Tetra was swimming erratically and didn't look good. He looked fine when I was feeding, but I'm pretty groggy at that point. Within 30 minutes, he was dead. One thing I noticed with the cory and the tetra was that the gills looked red and inflamed, almost bloody. They did not have any white spots or anything on them, so I don't think it was ich. I'm thinking that maybe whatever was infecting the gourami got to the other two fish, but for whatever reason it took a week to kick in. Any help or guidance would be appreciated. If its something like that, I'd just like to prevent it from spreading to the other fish. Don't want anymore deaths on my hands.