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Dennis Woollum
04-16-2005, 09:08 PM
I have a biofalls unit installed with a 2" bulkhead that came with it. The total outside bulkhead diameter is 3 3/4". I now need to install a 3" bulkhead out the lower rear of the biofalls so I can gravity feed into it from bio tanks. I can only find one at a local koi shop that is 5 3/4" diameter which will not fit as the biofalls box has a lip protruding outwards about 5 1/2" up from the bottom and the larger bulkhead securing ring will not fit.

Does anyone know of a slim profile 3" bulkhead that is no more than 4 1/2" to 5" outer diameter.

Charlie_23456
04-16-2005, 10:06 PM
Dennis, I got mine from AZPonds http://www.azponds.com/hose.htm. Dont remember the outside dimensions but it I had to cut a 4.25" diameter hole for it. Can you trim one of the sides of the bulkhead flange so it fits without weakening the bulkhead?

Koin-Onia
04-16-2005, 11:12 PM
How about a uniseal?
I have a biofalls unit installed with a 2" bulkhead that came with it. The total outside bulkhead diameter is 3 3/4". I now need to install a 3" bulkhead out the lower rear of the biofalls so I can gravity feed into it from bio tanks. I can only find one at a local koi shop that is 5 3/4" diameter which will not fit as the biofalls box has a lip protruding outwards about 5 1/2" up from the bottom and the larger bulkhead securing ring will not fit.

Does anyone know of a slim profile 3" bulkhead that is no more than 4 1/2" to 5" outer diameter.

nicco
04-17-2005, 12:49 AM
I have had good luck just drilling a hole the right size for a pipe, say four inches and bonding it in place with epoxy putty. That's how the drains on my vortex tanks are attached. My thought was that they'll never be removed so why bother with a bulkhead fitting at all? Of course once you have it bonded it isn't going to be movable at all so you have to get the orientation and height right first time.

Harveythekoi
04-17-2005, 01:01 AM
Requires a 4" hole. The seal will stick past the hole a ¼" at most. The hole size for a 3" bulkhead is 4½". The flange on that extends way beyond the actual hole though.

Nicco bought stock in epoxy putty so he's really pushing it's use now. :yes: :yes: But it does work well. And it gives you more options for connecting things.

Garrett

seanmckinney
04-17-2005, 05:29 AM
Have a look at those in the upper right photo of this page (http://www.koicarp.net/pvc_plumbing/connectors.html). These are of Japanese origin, well the name on them is, and I doubt the UK market is big enough for it to be the only market so they or similar are probably available in the US

Dennis Woollum
04-17-2005, 09:53 AM
Good ideas! I installed 4" toilet flanges on 55 gallon drums with GE silicone before. I wonder if they make those in 3".

I am considering a Uniseal but the pipe is at the bottom of the box and there is about 18" of space between the box and a 2X12 retaining wall that the pipe will pass through about 3" above the ground. How difficult will it be to force the pipe through at that low angle.

Sean, I will e-mail East Riding to determine the outer diameter of the flange.

seanmckinney
04-17-2005, 10:30 AM
If you can wait until tomorrow I'll measure one for you but it's a horrible day here today and I dont fancy getting cold and wet. The OD is at a guess between 7" and 8", the hole in the tank is the OD of the pipe.

seanmckinney
04-18-2005, 08:26 AM
170mm, 6.7"

Kent Wallace
04-18-2005, 10:09 AM
Here's the cheater method for a bulkhead. Use a male and female threaded PVC coupler for electrical conduit. The threads on electrical PVC are straight and not tapered pipe threads so they will butt up tight. Bore the hole very tight to the threads because there is not much shoulder and urethane them together through the hole. I've never had one leak yet. :cool:

Dennis Woollum
04-18-2005, 11:26 AM
Sean, it was only 68 degrees here yesterday...Had to get some work done.

Kent, how much of a lip on those connectors? Is there room for a gasket of some kind. This will be buried and I want to ensure no leaks.

seanmckinney
04-18-2005, 12:05 PM
Talk about rubbing salt into a wound "it was only 68 degrees here yesterday" you have no mercy :rolleyes:

Dennis Woollum
04-20-2005, 12:08 PM
I know Sean! Actually, I just passed on the warmth factor that those Floridians pass on to the rest of us when it's 85 down there in winter and were chilly or freezing our keesters off.