OK, I'm sure the dorsal fin has succumbed to fin rot. I'm a little depressed that he ended up with it….i do a twice weekly 40-50% water change and I have a heater keeping the temp stable at 78 but I guess that just didn't work. He did undergo a lot of stress when we went on vacation….being moved tank and all to my mom's house for a week, but there was nothing I could do about that. I was always told bettas were hardy fish and I'm not so sure about that, honestly.
Obviously, this rot is no longer mild…his dorsal is almost completely gone. Should I use tetracycline? I put an IAL in his tank today. He is due for a water change tomorrow, so I'll do that….should I step up water changes to every other day or something? I also read on another betta site that I should be aging his water changes….I used to do this, but I stopped. Maybe I should start again?
He is in a 5 gallon Aqueon tank, filtered. We use Prime as a water conditioner….should I switch to Stress Coat?