I had my Betta, Elton, in a three-gallon tank aquaponic tank. I had been testing the water and 0 ammonia 0 nitrite, and tiny bit of nitrate, temp 78 degrees.
Elton never seemed all that comfortable, but then again I only had him a week. The first couple days, he seemed interested in me but reserved, he'd come up and check out my finger, flare up at things on a regular basis. Then he became constantly lethargic, barely moving, would just lounge at the top of his tank. He never did eat anything (pellets or freeze dried blood worms). I cautiously took this all as him just settling in.
Then I started noticing chunks of his tail missing, it seemed like he might be chewing on it, and then he got SBD... but not super severe. He could get around okay, he would swim sideways, and then stop and he'd right himself. No sinking head first, and he was able to move around okay.
I read as much as I could on SBD (and internal parasites, and external, and popeye, and dropsy...), and thought maybe it would be best to put him in a smaller tank, and I can be sure that he's not constipated or anything, and if he does have issues, he can still easily get to the surface for air. So I did that, I tried to give him the thawed pee (with skin removed) he wouldn't touch it, even though I did get him to chase after it some. After a day, I decided to try an epsom salt bath, since I could see he hadn't passed anything... and that's what the advice said to do. Did that for 15-20 min, returned him to his little tank. He was listless, not moving, would avoid me at all costs (I put a little plant in there, his heater, and put a wash cloth over a corner, since there wasn't any place for him to hide, he never left that corner).
Anyway, long story short, I came home today and he was dead. I feel horrible, because I don't know what I did wrong, or what more I could have done. I'm still very much new to all of this, and am trying hard, but now I'm starting to wonder if I did too much? Should I have just left him in his tank and kept an eye on him? Could it have been all the stress that got to him in the end or something else?