How to figure out overflow and return pump?

[dc_909]

I am looking into a 280 tank, but was wondering how do you get the amount of water that flows into the overflow and the amount of water returned to the tank to be equal.

Is there a standard size for a drain and return pipes?
Or do you just adjust the flow of the return pump to what the overflow can handle?

 

[Travis L. Stevens]

You make sure that the bulkhead size is large enough to handle the pump. Then gravity takes care of the rest.