Quote Originally Posted by alton View Post
The mag 18 I had did not pump 1800 GPH, it was more like 800 at a 5' lift.
Stay away from the mag's if you're looking for flow. Alton's right. I just put a mag-12 as a return on my 90. The specs said 800gph at 5', but I measured it and it was closer to 600gph. They are very quiet when used under water. But can't handle head pressure.

I've bought 2 iwaki's in the last 10 years. One's used as a spare. Both (40rlt) still work and will each put out about 750gph at 5'. They're not the quietest pump out there, but very very reliable.