I'm going to avoid the trollbait and not get into the economic discussion of caring for a fish.

We have cut down his feeding considerably. He's now getting only a pinch about once a week. His bowl is generally cleaner than it was in the past (he has a bowl, not a tank; there's no filter, etc, because I'm not buying a $20-$30 tank for a $5 fish, plus his bowl is pretty tits.) Blonde Box of Rocks is keeping the water changed more regularly.

So far, Percy is hanging in there. Every once in a while he will have a burst of activity, and it seems that his fins are more active now than they were when we first got back (it's more rare that he is deathly still now, whereas he was mostly immobile a week ago.)

What can I expect in terms of improvement? Will he recover from ammonia poisoning or is it just impending doom at this point?