bulkhead flow rates

[slick]

Does anyone know the flow rates of a 2 inch bulkhead?

 

[eugenecjr]

Close to 1000 GPH would be my guess. Although a bulkhead that size is not all that common. a Bulkhead of a single 1 1/4" is about 600 GPH and if you need more they will usually add two 3/4" and then up from there. This is my estimate though, you may want to get a second opinon.

 

[pmauro]

Is there a formula for overfolw rates? I have two 1 1/4" overflows and two 3/4" overflows and need to know the total flow capacity so I can adjust my return flow to not drain my sump

 

[slick]

It would be drilled in the bottom of a 8x8 overflow box. Yes it is a drain line. So around 3000 gph?

 

[eugenecjr]

My opinion, but I think that 3000 gph is really high.

 

[slick]

Thanks for the help Big Mac
The tank I'm talking about is a 240 with a 8x8 overflow in each rear corner. I just want to make sure I can get enough flow to pump enough water that I don't need powerheads. I'm not exactly sure what a closed loop is could you ellaborate on that for me? What size/s would you recommend I put into the overflows? I don't have a pump yet but I was going to shoot for one around 3000 gph+