Just bought a 135 gallon tank set-up. The sump seems small,in fact old owner mentioned in case of power blackout..don't fill past here so it doesn't dump water in house. Has a"Little Giant" pump(in line only), sump, sterilizer,and I don't know term..final filter he said churns anything left. This is my first system of this type and I want to set it up right. How large should sump be? Thanks, Jim
