I have found a 20 gallon long with gravel, a filter (will sell it) and a bunch of decorations for $50 cad! Super happy an excited.You can definitely put 5 bettas in it. If she won't take care of the fish, then she should just give them to you. The good thing about divided tanks is that taking care of multiple bettas is pretty much the same thing as taking care of one. You're only heating/filtering/balancing the chemistry of one tank, and doing maintenance on one tank also. My setups cost roughly 60 each, and I'd be spending the same whether I had 1, 2, or 3 fish in it. By having it divided you're actually kind of getting more mileage for the money spent.