What size return pump??

[SpikesReef]

So I have a 1" pvc bean animal setup. The drop is about 42". I have two questions...
1- how do I find out how much the plumbing can handle?

2- am I good with a return pump as long as the gph is less that the max amount of flow that the overflow can handle?

Any insight is much appreciated!

 

[Reefing Madness]

#1-
http://flexpvc.com/WaterFlowBasedOnPipeSize.shtml

#2- Yup

 

[hybridazn]

Keep in mind that with a bean animal the full siphon can and will pull tremendous amounts of water. Just buy a return pump rated for the flow of the pipe, you will have headloss from the return.