Need prompt help - sick betta!

[Amehzes]

Housing
What size is your tank? - 2gal
What temperature is your tank? - 82
Does your tank have a filter? - No
Does your tank have an air stone or other type of aeration? - no
Is your tank heated? - yes
What tank mates does your betta fish live with? - A live plant

Food
What type of food do you feed your betta fish? - Hikari Betta Bio Gold
How often do you feed your betta fish? - 2 pellets twice a day

Maintenance
How often do you perform a water change? Once/twice weekly
What percentage of the water do you change when you perform a water change? 25 - 50%
What type of additives do you add to the water when you perform a water change? - Either pre-mixed betta water, or water conditioner

-When I change the water, I only use Wal-Mart's gallon spring water.
-I'm a college student stuck on campus, so I don't have proper water testing materials, thus I don't know any of the parameters.

Symptoms and Treatment
How has your betta fish's appearance changed? - Fins clamped, color dulled
How has your betta fish's behavior changed? - He has a bit of loss of appetite, I think. But when he does try to eat, he seems to involuntarily spit it back up. When he swims, he twitches a lot. He doesn't swim often; he spends most of his time resting at a diagonal slant (head by water), with little to no movement.
When did you start noticing the symptoms? The past 2 days.
Have you started treating your fish? If so, how? - I put in a little Bettafix
Does your fish have any history of being ill? - I got him only 3 weeks ago, but hes seemed fine until now. I noticed a small few twitches while he was still in the cup at the pet store when I got him, but I thought nothing of it.
How old is your fish (approximately)? - Well, Ive had him for 3 weeks, but I don't know his actual age.


So, I'll try to break my problem down as best as I can.
About 3 weeks ago I went to the pet store and got a second betta fish, since I was so in love with my first. Since I didn't have a tank ready, I used a little half gallon or so pet keeper until I got a two gallon tank for him. When I put him in the temp tank, it had gravel, a live plant, and a little figurine. No heater or filter or anything. The water was room temp and he seemed fine with it. After I put him in, he was stressed, so I put a towel over the tank to eliminate outside movement, and that night he seemed fine. He even blew a bubble nest over night. He stayed like this for about a week and a half, and he seemed perfectly content. I filled the temp tank with a bottle of the betta water, and some spring water. I didn't change the water for the week and a half he was in there, but he seemed to stay perfectly healthy and happy. As winter break came to a close, I had to move him from my home to my home, 4.5 hours away. He was transported in a clear Slurpee cup so he could sit safely in my cup holder. That night I set up the tank, rinsed all of his new decor for the new tank, etc, and set it up. I put a heater in too. After a few hours, the water temp was about 76, so I put him in since I felt bad about leaving him in a small cup overnight. He seemed fine with it, and explored his new surroundings. That was a few days ago. Yesterday morning, he refused his food, and started having his fins clamped in, and became less responsive to my presence. I wasn't sure what to. By the end of the day he looked more sick and dull, and began the twitching and such. I changed out about 30 % of the water, put in conditioner, and put in a different heater to make the tank a bit warmer. I placed him back in and it hasn't seemed to help much. I read that twitching may be from velvet or external problems, so I gave him a bit of bettafix overnight. Today, he has been mostly not moving, and when he does its abnormally spastic and twitchy. He's tried eating, but the food seems to come right back out of him. He then chases after it, and attempts to eat it again, but the attempt fails, and the process continues for a few seconds until the food floats too far down. When its too far down, he just swims back up, and rests at an angle. (I have been removing the uneaten food). He has been sitting like this all day. He hasn't blown anymore bubble nests, and doesn't respond when I stick my finger near the glass like he used to. He also doesn't seem to have any external problems, no gold dust, white spots, fin problems, or scale problems.

I apologize for the length of this, but I'm very worried about him, and I'm not sure what to do. Help?

[Adastra]

Usually what causes fish to become sick is exposure to stressful environmental factors that weaken the fish's immune system, making them susceptible to disease. The history you have given us actually makes it fairly easy to pinpoint the start of this--and that is the fact that you did not change the water for a week, and then transported the fish soon after.

Unfortunately this string of events left him vulnerable to infection. The Bettafix will absolutely do no good in this situation, it is an antiseptic and healing agent that is for open wounds and fin damage. It is also potentially harmful to your betta's labyrinth organ--what he uses to breathe air from above the surface of the water.

I would do a 100% water change to remove the medication from the water. Make sure that you take water from the tap that is the same temperature as your betta's water or if you have aged water, heat it in the microwave until it is the same temperature as the water currently in the tank. If you use the microwave, you need to stir the water throughout the heating process and be cautious not to overheat the water.

Always acclimate your betta to the water slowly--first, float him in a container until the temperatures equalize, then pour out and add water to the betta's container (bag, cup, etc) in increments to help him adjust to the new water. Do this over the course of about 20 minutes. This will minimize the stress of being introduced to new water without any medication.

You should be changing the water every 3 days. 100%. None of this partial changes once a week business--it is not sufficient to keep your fish's water clean, and it is part of why he became ill in the first place. Only filtered, cycled tanks can thrive on partial changes alone. Once he is in clean, unmedicated water he should show more accurate symptoms. Unwillingness to eat and lethargywithout external symptoms generally points to a few possibilities--one being stress from temperature fluctuations and ammonia poisoning, another being an internal bacterial infection, and possibly some internal parasites (although IPs would not present such dramatic symptoms).

Perhaps you should try some more enticing food, such as frozen blood worms (not freeze-dried). They are available in the freezer in the fish section of most pet stores--they are higher in protein and even sick fish go nuts over them. Hopefully he will be able to get those down easier. You can also soak the pellets in a little tank water and break them into smaller pieces--this will make them easier for the fish to eat and digest.