Hole Size vs Bulkhead Size

newsalt · 04/20/2009, 01:35 PM

There are two hole pre-drilled in the bottom of my 180g. The larger one is about 1-5/8" dia and the second is about 1-5/16" dia. When I started looking into bulkhead fittings for these holes, the pipe size a bulkhead to fit into these holes is small. For instance to get a bulkhead to fit into the 1-5/8" drilled hole, the pipe size is 3/4". IS this right. Do I get that size bilkhead and then enlarge the pipe immediately before and after the bulkhead?

nano mania · 04/20/2009, 01:41 PM

You need to use the same size pipe as the bulkhead fitting.
I don't think there is a benefit to using larger pipe if the fittings don't match.

THE ROOK · 04/20/2009, 02:03 PM

www.savko.com lists hole size vs bulkhead size. You want the sch40 bulkhead page. They're also sell bulkheads pretty cheap.

I don't think you'll get much of a gain by running larger plumbing after the bulkhead. One thought may be to use both for drains. One as the main & the other as a backup. Then simply go over the back with a return.

cdbias2 · 04/20/2009, 05:52 PM

Instead of glueing a piece of PVC inside your bulkhead and reducing the internal diameter. Try and use clear vinyle tubing as a coupler on the outside of the bulkhead to the same size diameter PVC. This will at least increase the diameter by 1/4". Just use a little silicone and a few hose clamps. It works great!

04/20/2009, 01:35 PM	#1
newsalt Registered Member Join Date: Jan 2004 Location: NJ Posts: 1,143	Hole Size vs Bulkhead Size There are two hole pre-drilled in the bottom of my 180g. The larger one is about 1-5/8" dia and the second is about 1-5/16" dia. When I started looking into bulkhead fittings for these holes, the pipe size a bulkhead to fit into these holes is small. For instance to get a bulkhead to fit into the 1-5/8" drilled hole, the pipe size is 3/4". IS this right. Do I get that size bilkhead and then enlarge the pipe immediately before and after the bulkhead?

04/20/2009, 01:41 PM	#2
nano mania Registered Member Join Date: Aug 2006 Location: Culver City, CA Posts: 291	You need to use the same size pipe as the bulkhead fitting. I don't think there is a benefit to using larger pipe if the fittings don't match.

04/20/2009, 02:03 PM	#3
THE ROOK Registered Member Join Date: Jun 2008 Location: Springfield, MA Posts: 2,100	www.savko.com lists hole size vs bulkhead size. You want the sch40 bulkhead page. They're also sell bulkheads pretty cheap. I don't think you'll get much of a gain by running larger plumbing after the bulkhead. One thought may be to use both for drains. One as the main & the other as a backup. Then simply go over the back with a return.

04/20/2009, 05:52 PM	#4
cdbias2 Appalachian Reef Society Join Date: Mar 2004 Location: Alum Creek, WV (No more) Posts: 1,433	Instead of glueing a piece of PVC inside your bulkhead and reducing the internal diameter. Try and use clear vinyle tubing as a coupler on the outside of the bulkhead to the same size diameter PVC. This will at least increase the diameter by 1/4". Just use a little silicone and a few hose clamps. It works great!