Help selecting overflow/pump combo

[Pezcado]

Hi all!
I am considering purchasing a lifereef single overflow. It says its average flow is 700 gph.
I am trying to figure what size return pump I might need.

I have a 55gal and plan on using either a 30 or 40gal sump.

Things I am not sure of are:

1. Is the flow rate of the lifereef overkill for my size tank?
2. How do I determine the "head" for the return pump?
3. What is the best method for return into tank? Spay bar?
Thanks to all in advane for your time and assistance.

 

[wickerj]

The flow rate from the overflow will match what your return pump is putting back in the tank up to the max amount it can handle. If you are going to use an external pump a CSL Velocity T2 would be a good size. If you're using a submersible pump look at a Mag 5,7 or 9.5 - Not really sure on the GPH on any of the mag pumps. You need to take into consideration any amount of head you'll have when you select the pump.
Good Luck,
Jeff