So I have a 2.5 gal, and I change 50% of the water on Wednesday and 100% on Sunday. Some personal issues popped up, and I was so stressed that I forgot to change 50% of my fish's water until Friday. I know, it's terrible, and I deserve any reprimands I get, but at least I didn't purposefully neglect him.
Anyway, despite the fact that I changed 50% of the water on Friday, it was looking a little meh yesterday, so I changed another 20% or so, just to be safe. This morning I fed him, and he was fine. This afternoon, I go to start his 100% water change, and he's floating at the surface of the water, gills wide open, almost like he was flaring. In a panic, I set up my 1 gal with about 1/2 tbp aquarium salt, my normal water conditioner, and a few drops of methylene blue (however you spell that). I scrubbed his thermometer, heater, and log and set them in there too. His gills are much better, and he seems to be swimming easier. I'm hoping that the 1 gal will heat up a little more than the 2.5 gal.
Any idea what could have caused this? Looking back, I do probably feed him too much, but he's not constipated (that I know of), and his tank was around 76-78 degrees. How should I proceed with his treatment? I'm gonna keep an eye on how much he poos, so how often does a betta usually poo?