View Full Version : Bulkhead to join sumps

01/20/2011, 03:03 PM
I need to daisy chain 3 sumps together. In order to maximize my stand space, I would like to link them as close together as possible. Actually butted up against one another is what I would like to accomplish. So I have been brainstorming for a way to use just 1 bulkhead to link two sumps together. I was told, that putting a gasket on the nut side of the bulkhead, in order to seal both sumps wouldn't work because water will infiltrate the threads and then leak. That made sense to me. I've been thinking, to combat the thread issue, that I could get heavy duty bulkheads that have the wider nuts, and use teflon tape to seal the threads as good as possible. Also, I would use a gasket around the bulkhead, that would be sandwiched between the two sumps, so hopefully if any water were to pass the threads, it still wouldn't have anywhere to drain out of the system. I would think that when the sumps are full of water they would make a good seal against that gasket. I would also place a couple of gaskets in between the sumps in other locations so there isn't too much pressure against that one spot. Anyone see why this wouldn't work or could foresee problems that perhaps I'm overlooking? Is there a type of bulkhead or other item that is designed to accomplish this task? Thanks.

01/20/2011, 05:05 PM
are the sumps glass? you can put a small tube between two bulkheads and put the threaded part inside and the seal on the outside the tanks to save on space.. but I would not hold two sumps together with one bulkhead

01/20/2011, 05:06 PM
also the small pipe should be flexable pvc if you can

GW Shark
01/20/2011, 08:19 PM
For acrylic tanks, you can put the gasket between the tanks and use the bulkhead to hold them tight together. Just make sure you drill holes in the two tanks that line up when you put them side by side. No teflon tape is necessary. I used a 4" bulkhead holding two 90 gallon sump tanks together for 5 years, with no leaks.

connecticut cichlids
01/20/2011, 11:31 PM
Uni-seals are your best friend

01/21/2011, 12:47 AM
The flange side of a bulkhead can seal a water volume from passing through because you have two flat walls sandwiching a gasket. Just like a valve cover gasket on a car.

What you want to do is seal the water from leaking out in between the sumps, so I would use the outside of the walls as the surfaces to seal the bulkhead. basically, put the gasket between the two sumps.

01/21/2011, 08:25 AM
The sumps will be acrylic. Scaryperson- What you had in mind, placing a gasket between the sumps, is the same thing that I had in mind. Except I was still going to use gaskets not only between the sumps, but also a gasket on the flange side of one sump and the nut side on the other sump. So I'll use three gaskets per bulkhead. Might be overkill, but once I setup the sumps I don't want any issues at a later time. Thanks for all the replies!

Claudio D
01/21/2011, 04:10 PM
Hi Yakfishin

Sounds good to me AS LONG as you fix the sump to a surface that will not vibrate neither deform under the weight of the water, if by any chance one of the sumps "settles" even a fraction of an inch you will generate stress that could break the acrylic

A small flexible pipe is the safe way



01/21/2011, 06:11 PM
most people cringe when I tell them, but i use a redundant siphon between 2 tanks in my sump setup. The setup uses siphon breaks like an overflow box. When one starts running slow the other picks up the slack. I have never had both fail at the same time and only had one back up/slow down maybe a handful of times over the past 2 years.

I re-prime the siphons before travel and during routine seasonal tank maintenance just like i do for my overflow.