Rescued a betta from Wal-Mart - do you think he'll make it?

Okay so I went into the belly of the beast - Wal-Mart. All to see if it was as bad as people say. The tanks looked decent oddly enough, but then I saw this one poor betta in a cup gasping for life in a pool of filth.

My mind went back and forth between "Do I give money to this crappy company but save a fish's life in the meantime?" Finally I opted to save his life if I could.

Anyway, his gill movements are extremely slow and long - like he is gasping desperately for oxygen. I slowly dripped in new clean water and slowly removed the old "water" (if you can call it that) over the course of last night. He is now in a half gallon bowl of 100% new water along with a Hydor mini-heater and lying on the bottom still trying to make his gills function.

What do you think the prognosis might be? I honestly can't tell; one minute he looks like he'll be dead within the seconds, and the next he swims around just slightly and then lands again to struggle breathing.

I assume he has serious ammonia poisoning and gill damage. Is this reversible? Might some time in the clean water let his gills and body heal enough that he can make a recovery? Is there anything more that I can do aside from just keep him in fresh water and a comfortable temperature?

No longer a wannabe betta rescuer now that I rescued one I suppose? hehe


Fins are actually quite good for his condition. They're slightly tattered but not anything that wouldn't heal in a few days. He still has color as well.

The gills are sticking out slightly. But that could be due to the fact that he seems to be breathing very slow and deep - sort of like how we would look if we were taking very long, deep, slow and relaxed breaths.

I haven't added salts or anything medicinal. Though I think I might pick up some aquarium salt on my outward mission today.

As of last check (a few minutes ago) he has left the bottom of the bowl and is now up near the top. I don't know if that's a good or bad sign. For one it could mean he's regaining strength, but on the other hand it could mean he's more desperate for oxygen. But then I'm afriad to add an airstone because he is so weak that even the light current of the water additions from my smallest syphon hose spun him around quite a bit.

Pictures

Here is he just when I got him home around 9pm last night:



And here he is just a minute or so ago, 2pm today: (image is a little distorted - it's a round bowl)