I've always loved the majestic beauty goldfish have. I love orandas and fantails. I've always wanted a tank with them. I realize they create a lot of waste so require large aquariums to keep a lot. But I was wondering what's the smallest size? I don't have a lot of room but I'm sure I can fit a 29gal or maybe even a 37gal. Would that be two small for 2 goldfishes? Do goldfish need to be kept in a larger group than two? Can they be kept happily by themselves?