Quest for the Perfect Fish.

I really want a pet fish. I was thinking about college and how much I'm going to miss my two dogs and so I decided to do some research. The only pets that are allowed at my dorm are fish and reptiles. Also, lately I've been playing with this application on Facebook called 'Happy Aquarium' and there's a bunch of fish that you can train and play with and such. I realize that in reality, you can't really train a fish. I still want one.
I like the idea of taking something living with me to college. Maybe I've gone off the deep end, but I guess it's like a comfort thing. The only problem is, I've never had very good luck with fish. I used to be a girl scout, and I'd get a fish every year from the carnival. One year I got about six fish and I took them all home and named them all after the dogs in my favorite movie at the time "Snow Dogs". But, one day I went in and there was only one left. So either they all ate each other, or they died and my mom flushed them without me knowing. The next time I got a fish, I didn't feed him very much. I was young, like seven or eight, and I didn't think he needed much food. So, he died. The next time I got a fish, I was so afraid he'd die like all the others that I fed him like five times a day. So, naturally, he died.
I haven't attempted to own a fish for about seven or eight years, but I think I'm more responsible now. I went to PetsMart or PetSmart or whatever it is yesterday with my friend and shopped for fish. I found a little black one with huge bulgy eyes and I instantly knew he was the perfect fish. However, this particular fish required a larger tank and a filter, which turns out to be kind of pricy for a spontaneous experience such as this.
Oh, I should probably mention that the death of my past fish may not have been all of my fault. My friend recently told me that filters are necessary with all fish. I didn't believe him, because my mom never told me I needed a filter, so it must be that I don't! Much to my dismay, I went to the store yesterday and asked the fish lady and she said yes, all fish need filters, except for the betta fish.
So, it was my lack of knowledge about aquatic caretaking, not my neglect or purpose.
Needless to say, I'm going to get a betta fish.