Bulkhead question

I'm needing to order bulkheads and a hole saw so I can finish my herbie overflow on my 75. Would 1 inch bulkheads into 1 1/2 drain lines flow enough to run a jebao dc 9000 or 12000 without any issues or would I be better off drilling for 1 1/2 in bulkheads?

 

Doesnt matter if you have 4in pipes. The 1in bulkhead will restrict all the flow.

However, those pumps are a bit much IMO for a 75g. You should aim for 7-10x tank turnover through your filtration.

This should also help. You will be looking at the green section for a drain line under gravity.
GPM/GPH Flow based on PVC Pipe Size, ie, How much water can flow through Sch 40 Pvc Pipe Size 1/2" 3/4" 1" 1.5" 2" 2.5" 3" 4" 6"

 

I lean towards 3-5x the display volume for a return pump so you keep the velocity down in your sump and do not create microbubble issues. This also allows detritus to settle in the sump so it can be siphoned, pumped or vacuumed out.

5x is a good number after headloss if you sump is suffiecient size like 30 gallons or larger but of it is 20 gallons or smaller you might want to drop down or the water velocity through the sump will not allow your skimmer to perform well and will carry bubbles back to your display no matter how many baffles or bubble traps you have.

Make up the bulk of your circulation or flow with powerheads, propeller pumps/wavemakers or a closed loop. The newer style pumps like the Jebaos and Vortex are very power efficient and small so move a ton of water for almost nothing compared to a larger return pump.

This might help answer some of your questions on bulkheads:
http://www.3reef.com/forums/new-hobby/bulkhead-installation-tips-111422.html

The 1" bulkhead will be a hydraulic restriction with 1.5" plumbing. You will gain a bit of flow over all 1" but not much and you may end up with a venturi effect from the restriction which could lead to cavitation, noise and bubbles. Probably not worth doing.

 

Thanks for the replies.

I guess I should have put some of this info in my original post

I'm moving my 55 gallon over to to a 75 gallon so dt circulation is covered, and right now I have a mag7 for my return pump on my 55 that I'm going to use on the 75 for a while. This will give me around 6x turnover on my 75. My plan is to plumb in a manifold (but not use it until I have a new pump) on the 75 to run my reactors off my return pump instead of running multiple pumps which is why I am looking at the larger pumps. Would the dc6000 give me enough flow for what I want to do?