Bilge Pump (10) by Rule Pumps®. Capacity: 2000 GPH. Voltage: 12 V. Engineered to commercial standards. The Rule 2000 is the best selling high capacity submersible bilge pump in the world. 1-1/8" (28.6mm) discharge outlet. Range of higher capacity standard bilge pumps are usually operated via a float switch or another level-sensing device, and give outputs from 1500 GPH (5678 LPH) to 4000 GPH (15141 LPH).