Unusual bulkhead design

[esoxlucius]

When I came back into the hobby in 2015 my first tank was around 180g. I got it from my local LFS who, at the time, but not no more, imported tanks from China. I had problems with that tank, it had to go back, but I salvaged a few spare parts from it and the original bulkhead was one part I held onto. Indeed, that original Chinese bulkhead is on my current 180g now.

I was writing down a list the other day of emergency spare parts I may need if I have a sudden problem and I realised that I haven't got a spare bulkhead should anything happen to that original Chinese one.

Thing is, I can't find one for love nor money. It is highly unusual in as much that it incorporates the drain AND the return in one component. You'll get the idea from the picture. The three quarter inch return goes up inside the one and a quarter inch drain stand pipe. I've always found this to be really strange because in effect the drain line is forever partially blocked with the return tube.

I can't get a spare from the original LFS as they get all their tanks elsewhere now. I've looked on line and come up with nothing. If an emergency happens I will probably have to put a standard bulkhead on for the drain and my return will have to go over the back if the tank.

I just wondered if anybody has come across this design before. By the way I have never had a problem with it so even though it's odd, it does work.

 

[Oughtsix]

Is the part that combines the "water in" with the "water out" actually part of the bulkhead? Or is it possibly a separate piece that is welded (glued) into a more standard bulkhead?

It is a cool design, I have not come across something like that before. I can see how it would make the in-tank plumbing quite a bit neater.

 

[fishhead0103666]

If anything perhaps you could have an exact replica made? Find a plastics company and ask them to make a replica perhaps.

 

[Zanzag]

its kind of ike the concentric deigns that HVAC guys use to vent/supply air to furnaces

 

[esoxlucius]

The part that combines the "water in" with the "water out" actually part of the bulkhead? Or is it possibly a separate piece that is welded (glued) into a more standard bulkhead?

It is a cool design, I have not come across something like that before. I can see how it would make the in-tank plumbing quite a bit neater.

It's an all in one injection moulded part made of ABS. The picture shows the bottom part of the bulkhead. The top part of the bulkhead, the part inside the tank, is your usual threaded design.

The picture below of inside my tank will show you even better what I mean. The outer clear polycarbonate tube is just so I can achieve bottom suction to pull waste out (if i take that away i will then get surface skimming). The middle blue tube is the drain stand pipe, and the very inner blue tube is the return., which, as you can see, comes up through the drain. You can see the 90 degree angle on the return which takes the return water to the other end of the tank.

And fishhead0103666 . If I took this part to an injection moulder to make me one they'd laugh at me. They'd hardly design a mould specially for an oddball part, costing ME many thousands of pounds, just for one!! Can you see how crazy that would be?

 

[Zanzag]

how is rhe return inside connected

 

[esoxlucius]

how is rhe return inside connected

That inner blue return pipe is threaded down the drain tube and at the bottom of the drain, which is now in the heart of the bulkhead, well out of sight, is a three quarter inch "nozzle" or something like that. The return pipe just fits nice and snuggly on it. Obviously you can't see what you're doing, you do it by feel. It just slots on, it's easy.

The thing I can't understand above all else is that we all know how important it is to keep your drains well open as blockages could spell disaster. And yet this unusual design is actually ensuring that the drain water is indeed hampered.

I don't run a huge turnover, that's key here I think. If I did my return line would then cause havoc.

 

[Oughtsix]

If you were desperate you could make a facsimile of the part quite easily.

Use a 1" Tee fitting then on one of the openings of the Tee put a 1" to 1/2" reducer with the "stop rim" of the reducer bored out so you could push a piece of 1/2" pipe all the way through the reducer and through the opposite opening of the Tee. Then join the Tee to a standard slip connection bulkhead. It wouldn't be as pretty but it should be functionally equivalent and reliable. Of course you wouldn't have to use 1" or 1/2" fittings and pipe, you could select what ever sizes that fit your purpose.

 

[Zanzag]

well 3/4 inch pipe inside 1 1/4 inch pipe leaves about the equivalent space of 1"pvc for your drain
im having a hard time finding a bulkead but look into low inlet elbows

 

[fishhead0103666]

So if I’m understanding it correctly it’s like a pvc pipe going down a few inches connected to an elbow joint, with another pipe going up the side of the elbow?