When he saw this Betta fish near the brink of death, he offered to take it off the store's hands for free. (He definitely didn't want to reward them for their terrible treatment.)
Unfortunately, he really was in poor shape. Kept in an uncovered community tank, his vulnerable fins were constantly nipped at by others until there wasn't much left.
To start the life-saving process, he put the Betta in a small tank for 2 weeks. He outfitted it with a heater, 6 grams of salt, and eSHa2000 (a maintenance medication for fish). He also changed the water almost every day.
These treatments caused all of the rotten parts to fall off, leaving him in truly bad shape. It even got to the point where the owner debated finding a humane way to end the fish's life.
He hadn't eaten anything in over a week, no matter what type of food was left in the tank. Things weren't looking good. One day he suddenly perked up and started eating. The fish was then moved into a larger tank with more space to swim, and even some little plants at the bottom if he needed a hideaway.