Quote Originally Posted by Paapaa
Just look at this graph:

http://www.cooling-masters.com/articles-33-16.html

The intersection of y-axis and a pump curve tells you the maximum head at zero flow. The intersection of x-axis and a pump curve tells you the the maximum flow at zero restriction. They both tell you very little about the actual performace which lies on the intersection of the pump curve and the system restriction curve - as shown on the image. The green curve represents one single WC setup. If you replaced MCW6000 with Storm the system curve would have a higher slope and the resulting intersection would show you less flow: the intersection would be positioned more to the left on the pump curve.

Just ask if you didn't understand something.
wow thank you very much. from that graph, i notice that the 50z is in the complex a little bit better then ddc isnt' it?