I did the whole fish tank in the dorm room thing and IME it was a HUGE hassle. Power cords/ strips that have to meet the building code ( they are pretty strict in a dorm ) the fact that the rooms are small so arranging them is a pain, and once a tank is set up and you have to move it again is going to be even worse. I love fish but I really don't recommend them in a dorm. On top of the maintenance they need and your studying/social life, it could cause issues with the roommate etc..... Oh and water changes those will be fun when you have to haul water from a community bathroom (ew) down the hall to your room.
sorry thats rambly, it was just a real pain to have one. My dorm room was fairly large (15X20ft) and had it's own bathroom and water changes still sucked.
Just some things to think about, best of luck