They are referencing the maximum flow rate of the JEP 1.5 which is 150 GPM at run out but that is not achievable on typical pool plumbing. With a typical 2" plumbing setup, the JEP 1.5 HP on high speed will produce about 90 GPM or about a 3 hour turnover. And yes at half speed, the flow rate is about 1/2 and power usage about 1/6.