Flow rate question

[slick]

Does anyone know the flowrate of a 2 inch bulkhead? I'm trying to decide on which size bulkheads to put in my 240. Any suggestions are welcome. My overflows are 8 square so hole size is not a problem. Also my returns are going to come in from the top.

 

[mlm]

Mine is a 1.5 inch on my 120 and it handles the flow of a Mag 24 with tons of room to spare.

 

[cboyfan2020]

I would guess around 1500gph max. 2 1" holes would be 700gph a peice so that is my reasoning. Could be wrong.

 

[slick]

Sump size is not a problem I will be using a large rubbermaid container. As far as pumps go I'm not sure what I'll be running yet but it will be a monster capable of returning water from both overflows. So you guys are thinking that 2 1.5 bulkheads would be enough?

 

[mlm]

Definitly. my one 1.5 inch is way more than enough for the mag 24 (2400 gph).

 

[dubba-r]

I currently have 2 - 1" drains and a Mag 24 on my 125G. The overflow cannot keep up with the the mag 24 pump. I would say i am putting around 6-8' of head pressure.
I just put a "T" on the return line, which i rerouted back into the sump to throttle the pump back. So i would guess 2 - 1" would give around 1500 gph. The mag 24 pushes a lot of water.

 

[shep]

Just a thought...I went into this when first setting up my 125. Called CPR about a few things and ask about this question in particular. I was told roughly 750gph per inch of pipe. I am running around 1050 gph (true flow) right now. To acomidate this smoothly I run a 1.75 in smooth flex tube. The one provided by CPR was like a vaccum hose and slowed flow considerably.
Hope this helps you.