OK, it looks like you have another thread about this too. I'm going to post a link so that people can view both threads: link to your previous thread
On the previous thread, you said that you do frequent water changes because his food "gets stuck in the rocks." To me, this indicates that you could be overfeeding him. Also, you said that you're giving him Betta-Min Tropical Medley flakes.
Foods that contain a lot of grains and fillers (wheat, corn, soybean, rice, gluten, etc) can be constipating. The Betta-Min Tropical Medley that you're feeding him contains "Fish meal, ground brown rice, torula dried yeast, shrimp meal, wheat gluten, dried potato products, dehulled soybean meal, fish oil, soybean oil, algae meal, sorbitol, lecithin, l-ascorbyl-2-polyphosphate (vitamin C). Artificial colors including red 3. Ethoxyquin as a preservative."
How often does he poop? What does it look like? He may be constipated and/or in need of better nutrition.
If this was my fish, I would:
- Fast him for one day.
- Add Epsom salt. Since you have a 2 gal tank, you can take a small amount of tank water, add 1 teaspoon Epsom salt. Stir until the salt is completely dissolved, then pour it back into the tank. (This will provide a dosage of 0.5 teaspoons Epsom salt per gallon.)
- About 12 hours after adding the Epsom salt, repeat the above process. Take a small amount of tank water, add 1 teaspoon Epsom salt. Stir until the salt is completely dissolved, then pour it back into the tank. (This will provide a combined dosage of 1 teaspoon Epsom salt per gallon.)
- Switch him to a high protein quality pellet food, such as New Life Spectrum Betta pellets or Omega One Betta Buffet. (I prefer pellets since they're easier to measure out. This means there's less chance of overfeeding, and you can determine exactly how much you're giving him.)
- It may take several days for the Epsom salt to do its job. Whenever you do water changes, premix the Epsom salt solution, by adding 1 teaspoon Epsom salt into a gallon of water. (This will maintain the 1 teaspoon per gallon dosage.) You can keep him in the Epsom salt solution for 10-14 days.
Edited to add: Could you turn off the light in his tank, and post another photo?
@tngirl - this doesn't look like the "mystery disease" (Mycobacterial infection) to me. The color change is different. In Myco, the fins turn gray, which indicates necrosis (tissue death). But, to me, boopers93's betta has an overall body change, which looks more like it's stress-induced.
@lilnaugrim - I originally recommended Epsom salt at a dosage of 0.5 tsp/gal. But I'm using my kindle, so it's difficult to see the photo. Since you think he may have popeye, I upped it to the standard 1 tsp/gal. (It's definitely OK to use 1 tsp/gal, regardless.) You did a good job offering advice!