Sump Pump Question

I bought a 65 gallon megaflow overflow tank including the megaflow 3 wet/dry filter. The site says the over flow runs 600 GPH rate and that I should use a pump that can return 2400 GPH

Is this right? Wouldn't it push too much water more then its draining down into the sump? I'm trying to find return pumps, please help and educate me on what kind of pumps I should use.

Thank you, Andrew

Dream Tank

HI everyone, i wanted to start by introducting myself, im andrew and i wanted to get a fish tank for a flowerhorn I will get later.
Ive read a tall tank is good for flowerhorn and wet and drys are good also so I wanted to get the all glass aquarium with a bulit in megaflow overflow. the dimentions are 4 Foot long, 18 inches wide and 29 inches tall. the back left of the corner is the overflow. heres a link http://www.aqueonproducts.com/products/meg...ow-overflow.htm

this is where im getting a little confused, is it the bigger the wet dry sump the better? or should I stick with the recomended sump? I would like to get bigger.

thanks,
Andrew