Overflow 'box' Using Pvc Pipes Only

[Fishfreak]

I stumbled upon a DIY overflow 'box' using only PVC pipes. Failed to find any info in RC. In rec.marine.reef, I was told it worked and is a self-priming design. No other info was provided. The designer's email address was invalid too.

Does anyone have any info on this? It looks like something that can be done up in less than half a day .... if it works that it ....

[ozy]

Look like a design by Escher...

Do you have the design in other views? I am very interested in making one if it works. There is a question though, in the centre, it looks like a "+" connector for the pvc pipes. As far as I know, there is no "+" connectors available. If that is the case, then there is no way for us to make one.

[FuEl]

I frankly see no use of the '+' connector.

[PornStar]

I'm constructing an overflow using PVC tubes only too.

Made a smaller scale one and in principle, it worked.

So am in the progress working on a larger one for my 3ft.

Will try to put up some pics when I'm done...but that's when I actually find the time to redo my whole tank again.

But you may find this useful.

[SpiderOne]

that is one funky lookin overflow

[PornStar]

I frankly see no use of the '+' connector.

which '+' connector?

the one in the background?

If that's the one, I would think that it's there to act as a control point for the difference between the pressure heads of the inlet and the whole overflow unit.

[Fishfreak]

Do you have the design in other views?

I recall the site has an animated view. Problem is I cannot remember the address. Gotta dig around. Will see what I can find.

. As far as I know, there is no "+" connectors available.

Ohh... can someone verify/confirm?

I frankly see no use of the '+' connector.

It looks an inlet to get the prime started and maybe later on a hole to stick a straw in to stop the gurgling sound if any. Also look like an outlet for excess water to flood the room!

But you may find this useful.

Better because it is simpler, but is this self-priming?

I'll see if I can find the old usenet threads on this. Its been a while since I came across this but didn't do anything because I was travelling most of the time.

FF

[ervine]

Interesting... but I don't see how you can start the siphon leh.... (i'm refering to the website) also, it looks to me like it can easily suck up a lot of air which would eventually kill the siphon...

[PornStar]

Interesting... but I don't see how you can start the siphon leh.... (i'm refering to the website) also, it looks to me like it can easily suck up a lot of air which would eventually kill the siphon...

Suck up air?

You mean the open end at the top of the system?

Tat is essential control mechanism for the self-control overflow system. Without that part, the whole system cannot self-regulate.

Better because it is simpler, but is this self-priming?

This system is not self-priming but it doesn't take much to start the siphon effect.

[Ian]

I've seen this last year and I think its a logical design. Never tried it yet but it should work fine.

[ervine]

i still don't see how you can get the siphon to start leh... excuse my "blurness"

[Fishfreak]

QUOTE 

Better because it is simpler, but is this self-priming?

This system is not self-priming but it doesn't take much to start the siphon effect.

Pornstar, what I meant was if the power goes off, will the design self-prime when the power comes on?

Posted on Sep 22 2003, 05:21 PM

  I've seen this last year and I think its a logical design. Never tried it yet but it should work fine. 

Ian, which design were you refering to? The funky looking one or the simpler one?

As for priming the funky one, I'd simply use a pump to 'force' water in. I do this to my SCWD closed loop to get it started after a water change.

FF

[PornStar]

Pornstar, what I meant was if the power goes off, will the design self-prime when the power comes on?

I'm sorry but I do not quite understand what you specifically mean self-prime. I only understand it from a canister filter point of view when stating self-prime.

For the pic that I had attached to my previous post, as long as there are no air pockets in the system to break the siphon, except at the open end, the overflow will continue to function as per normal when water is pumped into the tank.

If there is no water going into the tank, the overflow ceases to function, vice versa.

i still don't see how you can get the siphon to start leh... excuse my "blurness"

When the unit is placed in the water, there will be an air pocket at the first 'U-shaped' bend.

The principle is to remove the air in that pocket so that it is filled with water to start the siphon.

This removal can be done via ###### the air out through a plastic tube or incorporate a normal control valve to allow the air pocket to disipate while water is filling up the tube.

The water level in the tank will always be the same level of the 'T'-joint at the open end. (basically at the tip of the 5th arrow from the left on the diagram).

I hope this makes things clearer.

The only problem I can think of with the funky one is starting of the siphon for the overflow. There should be an outlet where air pockets can escape from the bends in the tube.

[yus75]

I'm sorry but I do not quite understand what you specifically mean self-prime. I only understand it from a canister filter point of view when stating self-prime.

For the pic that I had attached to my previous post, as long as there are no air pockets in the system to break the siphon, except at the open end, the overflow will continue to function as per normal when water is pumped into the tank.

If there is no water going into the tank, the overflow ceases to function, vice versa.

When the unit is placed in the water, there will be an air pocket at the first 'U-shaped' bend.

The principle is to remove the air in that pocket so that it is filled with water to start the siphon.

This removal can be done via ###### the air out through a plastic tube or incorporate a normal control valve to allow the air pocket to disipate while water is filling up the tube.

The water level in the tank will always be the same level of the 'T'-joint at the open end. (basically at the tip of the 5th arrow from the left on the diagram).

I hope this makes things clearer.

The only problem I can think of with the funky one is starting of the siphon for the overflow. There should be an outlet where air pockets can escape from the bends in the tube.

hmmm quiet interesting....but where to get all those pvc pipes n joints....???

[FuEl]

Wow..nice and simple overflow...hehe....maybe I should try that out.

[nutx]

Hi,

I've done up the piping as per the diagram above.

The siphon is working, but the flow rate is very slow. Anyone can help me on this?

I'm using 1 inch pipe, is the diameter to wide?

Thanks.

[Fishfreak]

Hi Nutz,

I contacted a guy in the US who built it too. He used 1" ID pipes and estimated his flow to be approx 480gph (~1800lph). He ouwld like to have a higher flow, closer to 1200gph, but didn't know how. he did not want to build two of those because of space constraint.

So, how did you get the unit primed for first time use?

Did the siphon hold if you simulate a pump/electrical failure?

FF

[Crab]

Hi,

I've done up the piping as per the diagram above.

The siphon is working, but the flow rate is very slow. Anyone can help me on this?

I'm using 1 inch pipe, is the diameter to wide?

Thanks.

I find 1 inch too small, resulting in slow flowrate. I've bought all piping to make 1 but no time to fix them together. It's 2 inches.

[nutx]

Hi...

I fill up the whole piping with water, then cover up all the outlets.

Then I remove the in and out (keeping the T-joint outlet closed).

This, will create a siphon effect, and water will come up at 'full speed' then I remove the T-joint outlet cap, and the whole piping become 'self-regulated', which mean the siphon will stop when the water level go below the inlet, and start again when the water level increase to above the inlet.

(err...hope you understanding what I'm talking...

Hi crab, my problem is that the water is not able to flush out, it is like slowly flow out. Could it be there are air bubble trap at the varies U junction that is affecting the effect, or the height of the joints play a part?

[Crab]

Hi crab, my problem is that the water is not able to flush out, it is like slowly flow out. Could it be there are air bubble trap at the varies U junction that is affecting the effect, or the height of the joints play a part?

Do you make your's this low?

(picture taken from internet)

[Limpc]

Hi all,

I have just completed this kind of overflow. Yes, I have done almost exactly the picture posted by Crab. Using 1.5" piping and my return pump is 2800l/hr. BTW, it for my hospital 2ft tank.

So far so good, it's self priming. Very neat and tidy comparing to an overflow box on the outside.

LimPC

[nutx]

Ops! ....If the height is a problem, then my sure got problem, as my is not that Low.

Will modify it and try again.

[yus75]

Hi all,

I have just completed this kind of overflow. Yes, I have done almost exactly the picture posted by Crab. Using 1.5" piping and my return pump is 2800l/hr. BTW, it for my hospital 2ft tank.

So far so good, it's self priming. Very neat and tidy comparing to an overflow box on the outside.

LimPC

do u do the 2 small black vent line too?? if so wat do u use....anyway i tink the inlet is far too deep.....m i right...???

[Crab]

Hi all,

I have just completed this kind of overflow. Yes, I have done almost exactly the picture posted by Crab. Using 1.5" piping and my return pump is 2800l/hr. BTW, it for my hospital 2ft tank.

So far so good, it's self priming. Very neat and tidy comparing to an overflow box on the outside.

LimPC

Could you estimate the flow rate it can handle? What brand is your pump? What is the actual flowrate in your setup? (2800 lph pump don't flow 2800 ltrs of water per hour when there's height/resistance)

I intend to make this modification, so it will skim the surface. Comments?

[Limpc]

do u do the 2 small black vent line too?? if so wat do u use....anyway i tink the inlet is far too deep.....m i right...???

Hi yus75,

Not too sure which 2 small black vent line you are referring to ? Can point out in the picture ?

The intake pipe is way too low in the main tank. Imagine the return pump malfunction, you will end up with a swimming pool on the outside and fishes dry swimming inside. Do not assume things dun fail. I'm always a strong believer of Murphy's Law.

LimPC