I might be picking up a 55ish gallon tank tomorrow, with all the supplies minus stand for $20. I was originall going to get a 20g but found this one for the same price. My original plan was to get only 1 betta, and transfer some plants from my 72.

Is it a bad idea to put a single betta in a tank this big?

Would I ever be able to add other fish to the tank over time, or just bottom feeders and such?