This Sunday, I went to Petsmart to grab some dog treats. I walked through the fish part of the store, and saw the Bettas. I then made a very impulsive decision. I talked to a worker for a few minutes, read a pamphlet, and bought a 1 gallon tank, some Betta Bits, some gravel, some water conditioner, and a blue male Betta. I brought them home, rinsed the tank and gravel, filled the tank, conditioned the water, and let the water sit until it was the same temperature as the water in the Betta's little container. I plopped him in, and set the tank near my desk. I experimental dropped in a few bits to see if he was hungry at all, and he wasn't ready to eat. I watched him for a few minutes here and there, and went to sleep. When I woke up in the morning, he was just sitting in the corner of the tank. I tried feeding him again to no avail. I wondered if the water was too cold, so I dipped a finger into the water. It seemed cold, so I turned on my desk lamp overhead to see if I could warm it up a bit before work. It seemed to do the trick, and he started moving around a bit. He shied away from my finger instead of following it, but I assumed that was typical and something he would do until acclimated to his new home. Got home, tried feeding him again, nothing. My morning was the same. After work, I stopped by Petsmart again, and bought a small heater, a small fake plant, and a little container of bloodworms, daphnia, and mysis. I put the heater in along with the plant, let the heater sit for a few, then plugged it in. Within an hour, the water was warmer, and the fish was moving around much more. He started relaxing and I could see his fins better. I went downstairs for a few, and left to go to a little get-together for an hour. I came back, hopped on my computer, and watched him while a few games loaded. In the middle of a session, I looked over and noticed him flailing in the water. He eventually stopped, nose down in the gravel. I was scared, and dipped a small stick into the water to see if he would shy away from it. He didn't move until I nearly touched him, at which point he flailed some more and settled. I had to answer a call though, so I figured maybe he was just doing some betta thing, so I went downstairs again. When I came back, he was white in some places. After a bit of Google-fu, I concluded he was dead. I left him there for about an hour more, just in case, but was even more white when I returned. I took some pictures, removed him, and flushed him. In the event he wasn't dead before, he is now.
So tomorrow, I'm going to buy another Betta. I dumped the water and gravel, rinsed the gravel for 10 minutes along with the plant, and cleaned the tank more. I filled it back up, this time with water from my fridge and applied the conditioner. I am now currently heating it to an ideal temperature, so that tomorrow I can get a new fish and hopefully have better luck. I'm coming to you guys to see if I can get a cause of death (to avoid it again) and to get any advice you guys have. I would like to have a happy, not dead Betta, and I'm pretty sure you can help. Attached is a link to a gallery with my tank setup and the fish itself.
Also, I removed the food after several minutes of him not eating it.
I don't really feel sad, just disappointed that I can't even take care of a fish.