Can someone point me to a link that describes pump performance a little better?

There is a chart, at the bottom of this page:

http://www.calpump.com/products.asp?category=4

But, what I don't understand is, how do you determine the flow rate in GPH if when using the pump listed, the maxium HT. of a water feature can be only 2 or 3 feet?

The chart says the pump can make the maximum head be 11 feet for example, with the P1600 pump at which point the flow rate would be only 220 GPH, but what if you are using a foam jet fountain, of which the maximum height can only be 3 feet or so?

Does this mean, that using a nozzle that is limited to 3 feet in height is automatically consuming the pumps flow rate so that it would be the same as if an 11 foot high nozzle was being used?

I'm a little confused.