Well, the mystery of what killed my Temeraire has been solved. My female
betta has come down with what appears to be a bacterial disease of some sort and is currently being treated with maracyn.
They were in a divided tank, so they did share water but did not live together exactly.
Tem was always very sensitive to everything. Other fish could take a random change in their environment with little effect, he couldn't. Once the temp dropped one degree in his baby tank (2.5 gal) and he about died. I had to get a heater to get him to perk up. So I'm guessing that the bacterial thing affected him much more severely and quickly because of that... he basically went from fine to dead overnight.
Second, my female is currently overcoming bacterial infection/fin rot. The water seems ok,
pH is a bit high, downing it gradually. Nothing else in the tank has changed, save that the male she could previously see through the divider has died.
But anyway, she is fat. Like, extremely. She's been that way for awhile, and I've really got no explanation except that she eats and eats and eats. I feed them once a day, only a small amount of crushed betta food (because there are tetras in there, and their mouths can't fit the whole pieces). She'll occasionally steal an algae wafer from the panda cory and otocinclus... anyway, she's fat.
The belly-bulge is uniform, likely not a tumor. She is definitely just a fattie. My question is this: how can I reduce her weight? She acts fine, but being that big can't be good for her -__-