A rule of fuel being half the NOS is a starting point but not a fixed rule. I had a 75 NOS and I believe a 25 fuel. It all depends on the tune and the car.
The fuel system will cope, I wouldn't be getting worried about that. If you're jetting high numbers then maybe an issue. Maybe have a chat with Mark.
So in the case of your question what size fuel, I had 25.
Will you be having bottle heaters, 1 or 2 bottles and size? Where are you installing the bottle(s). Are you having pressure and temp sensors for the bottle(s)?
The minimax is a basic controller. I had the Max Extreme Street controller, has great functionality.
DONT RUN THE NOS WITHOUT HAVING YOUR CAR TUNED BY A PRO!!