can someone tell me want the two smaller holes are on this freshwater tank? I'm assuming the bottom one is where I pull the freshwater from connected to a waterpump? And the gray one is where I fill the water. And I'm assuming the top one is a vent but I'm not sure. Also are these the only 3 ports on this tank? I can't see the rest with out chopping the floor up.
Any help would be great . Trying to set up fresh water.