Thinking about adding frag tank to my system. The system includes 500g display with 100g sump and 100g fuge. Should I make this new frag tank separate system or run everything of one system? Also for the frag tank I am going to order new tank and I am not sure where to place the overflow, center or at the end? Any and all suggestions are appreciated. Pictures are very welcome. I am ordering the tank soon so need to make my mind quick. The tank is going to be 84x36x15 high.