Thank you very much for your reply! The temperature is usually 68 or 69. Unfortunately, I haven't tested the chemistry lately (and, unfortunately, it wouldn't help to do so now--I've been doing significant PWC's every day since this thread began). I'm using a Tetra Whisper 40i on a 20 gallon Long tank. It's bare-bottom, and the frog is the only creature in there. She eats Reptomin pellets. I've tried earthworms before, but she normally just got so excited she ended up kicking them into the filter. If it's any help, she is 8 years old (which, from what I understand, is well below the average).

The frustrating part of all this is that her "normal" appearance is completely at odds with her behavior...While her breathing is at the same intervals as it was before this, it's like she's taking "half breaths" compared to how she's breathing now. She ate 1 pellet the day before yesterday, and hasn't eaten since. Although she did poop today, so she probably has a good amount left in her stomach.

Before, she used to swim constantly. Now, the few times she does swim it's very awkward-looking. It's like one of her legs will move, there will be a 1-second delay, and then the other one will move. Apart from that, she has developed a weird twitch that looks like a combination of a big hiccup and The Worm. Sometimes, that's the only way she can start "swimming" along the bottom.

However, I should clarify that her back legs work together just fine when she uses them to jump/push off from the floor to the surface, when she needs air. After moving around at the surface for a minutes or so, she goes back down, scuttles around on the floor a little bit, and then returns to her cave. Finally, when she moves around on the floor, it's like she thinks there's food down there (again, there usually isn't). She keeps directing her hands at her mouth on the floor, but stops when she gets to the surface (where food usually is). It's like she's seeing the world upside-down.

She doesn't have any redness or problems going to the bottom, so for me that rules out Red Leg or bloat.