I bought a female betta from walmart since she was in horrible condition and once she was better I put her in my aquarium. She ended up being highly aggressive and attacked two of my females(me female Cambodian and blue dragon). Her side had been raw and looked really painful and although I tried treating it with a little aquarium salt the wound just kept getting worse and she passed away last night :(
Here's what the wound looked like at first, really not too bad more just missing the scales. It must of been infected because it kept getting deeper and deeper :(