Does he skim the surface when getting a new head-full of air, kinda motor-boating along blowing bubbles?
No, though he will take random gulps sometimes (while he's in the water). He's always done that, but he does it more lately. Since last night he's also been starting to flare a little, which I thought was a pretty good sign. He doesn't flare his fins out, but if I come over to his tank unexpectedly he'll flare out his gills.
The water has been changed 100% something like 4 times in the last five days, and even now he's in 2.5 gallons (and is fasting so pretty much no poo) so I don't know that he could be making the water bad quality fast enough to hurt him. I'm in Los Angeles city though, so the tap water isn't great. I let it sit overnight in addition to treating it, before I give it to him.
The medicine I've been giving him is supposed to be 1 dissolving wafer/10 gal...but I dissolved it in 10 tsp instead, and put 2 tsp in his changed water.
Today he seems pretty active--and angry, b/c he keeps half-flaring at me. I think he might be hungry. I can't tell if he's having those muscle spasms or not, because he can go still when he wants to, but he also has a pretty choppy movement *sometimes* when he's swimming, and he will sort of dart his head around (like he's doing the snake) when he's trying to stare me down (when his gills are open).
He still hasn't discovered the hammock! But at least he found a way to sleep on/in the cave comfortably.