# Overflow/Compact PVC siphon Q



## Bushpig2 (Nov 29, 2010)

Hello all!

I saw and built the compact PVC overflow and it works great....until i kill the system. The pump turns back on but the siphon is gone. I got the idea from a MFK post that was linked from here and the design the guy made supposedly kept the siphon but mine wont for some reason.

1.) I haven't drilled the hole at the top the outer 2" PVC, is this necessary to keep the siphon during power outage/full system stop?

2.) I can start the siphon quite easily by shutting the ball valve and filling the outer 2" pipe with water, then sliding the inverted "U" of 1" into the outer 2" pipe, because of water displacement it fills the "U", i open the ball valve and starts the flow of water. My second question is do i need that airline tubing at the top for any other reason than to start the siphon?

I apologize for the lack of pictures, but I'm at work and my Flickr account inst working, and i know how we all love some pictures of anything fish related, but here's the Link for MFK where i got the idea and about half way down the page is a MS paint drawing of what it basically looks like.

To all those who haven't read it and ask how the siphon is kept, the 1" that extends down into the outer 2" goes past a "T" coupler and holds a certain amount of water. I have that incorporated that into my overflow, but for some reason it doesn't keep the siphon.

Any help/comments appreciated!

Thanks, Pat


----------



## Guest (Feb 4, 2011)

Yes you do need to drill a hole at the top U. Also you need the airline tubing and a check valve. The hole around the tubing will need to be siliconed. The whole reason the siphon should restart is because once you suck air out and then the check valve keeps out the air and th siphon will restart because there is no air in the tube.


----------



## Bushpig2 (Nov 29, 2010)

From my understanding, the airline tubing and check valve is to start the siphon, I don't need help starting the siphon, I have that covered and can start the siphon easily, or am I not understanding what your telling me? The problem is once the siphon is started and the system is running and then I shut it down and the siphon is gone. It should start back up in case of a power outage as it was designed.


----------



## Guest (Feb 4, 2011)

You're right the airline and check valve are for starting the siphon but it also keeps the air out and the air that is getting in is what is not allowing your siphon to restart. The airline and check valve air mandatory if you want to be able for the siphon to restart. I have this same system and it works but the airline and check valve are needed also you need to silicon around the tubing and PVC.


----------



## Bushpig2 (Nov 29, 2010)

Ok, got it. Ill pick all those parts up this weekend. What about the hole drilled on the top of the outer 2" that doesn't have an airline tubing? Is that needed as well? And thanks by the way


----------



## Guest (Feb 4, 2011)

Are you talking about the vent when you say outer 2"


----------



## Bushpig2 (Nov 29, 2010)

Yes, the outer 2" pvc pipe


----------



## Guest (Feb 4, 2011)

Yeah there will need to be a hole drilled in the vent pipe as well


----------



## krfhsf (Dec 25, 2008)

I would have the T on the big pipe on the back up higher. If it's low like that it will drain the big pipe in the tank and lose the prime. It should flow the same but help keep the prime better.


----------



## Bushpig2 (Nov 29, 2010)

I installed the airline tubing and drilled the outer 2" vent hole. I'm sure I have the check valve in the right way, but is there a ceratin direction the check vavle goes? I'm sure I have it in right, I'm able to suck air through the intake, but I just wanna be sure.

I read about moving the "T" up and I incorporated that into my system, I think I have about 4" from the bottom to the outlet of the "T".

Thanks again


----------



## Guest (Feb 6, 2011)

My check valve came with an arrow of the direction on it but if you can suck out then nothing should go back in


----------



## Rhinox (Sep 10, 2009)

^^^This is what you're building, yes? Just wanted to make sure I see whats going on.

If you can get the siphon started without airline tubing, then I don't think the airline tubing is necessary. If air getting into the smaller pipe during operation, then you have to manually suck the air out either way so I don't see whats so magical about the airline tubing and check valve to keep the siphon automatically.

You do need to make sure both ends of the smaller U-tube stay submerged. So your outlet has to be above the level of the bottom of the smaller U-tube on the both sides otherwise you'll lose siphon when the power goes off.


----------



## Bushpig2 (Nov 29, 2010)

Yup, that's exactly what I built. I put the airline tubing in there anyways and I think it was the fact that I didn't have the vent hole on the outer 2" pipe. I drilled the hole, but I haven't been able to really test it cause I drilled it before I left for work.


----------



## sheldon_goldwing (Sep 27, 2010)

how quiet are these? what GPH does it do?


----------



## Guest (Feb 9, 2011)

Mine is very quiet. It's actually quieter than my marine land 350.


----------



## Guest (Feb 9, 2011)

.75 - 325gph
1 - 600gph
1.25 - 900gph
1.5 - 1300gph


----------



## Bushpig2 (Nov 29, 2010)

I drilled the vent hole in the outer 2" pipe, put the airline tubing in and the siphon doesn't hold after 20min or so. Its also pretty loud, if I plug the vent hole, it goes quiet, if I unplug it it gets all gurgly and sound like pockets of air gets sucked into the pipe. I wish I had time to post pictures up to give you guys a visual of what's goin on, but work sucks pretty bad right now, the hours are crazy. Hopefully when I get home ill have time and can post pictures up


----------



## Rhinox (Sep 10, 2009)

It still sounds to me like your outlet in the 2" pipe is lower than the bottom of your 1" pipe on 1 side of the other. Lets see if I can sketch up a couple quick paint diagrams to show you what I mean.


----------



## Rhinox (Sep 10, 2009)

Actually its taking a little too long to draw what I mean to explain it any better than with words but do you understand what I'm basically saying? Check and make sure your outlet of the 2" diameter pipe is at a higher level than the bottom of the 1" pipe on both sides.

The system should suck air if its working properly the outlet of the 2" pipe is a gravity overflow if it doesn't suck air it will full siphon, drain to quickly, gurgle, fill back up, full siphon, drain quickly, gurgle, etc. The size of the vent hole should tune that to keep the keep the outlet from going 100% full siphon followed by full loud gurgle - just like a standpipe.


----------



## sheldon_goldwing (Sep 27, 2010)

Just to clarify, what you are saying is that the Ã¢â‚¬Å"TÃ¢â‚¬Â


----------



## Bushpig2 (Nov 29, 2010)

Ah, ok, I get what your sayin, ill check hat when I get home, that might be my problem, thanks


----------



## Bushpig2 (Nov 29, 2010)

So *** fiddled with the overflow, made it smaller and more compact. Unfortunetly it doesn't work. At all.

Even though Ver. 2 smaller in size, the design is the same as Ver. 1. The problem with Ver 1. was that the 1" intake tube wasn't long enough to reach past the outer 2" PVC pipe that was supposed to keep the siphon in case of a power outage, so after 20 min or so the water ran out and the siphon didn't start back up.

Ver. 2 came from wanting to get rid of a lot of the 2" PVC i had running down the entire back corner of the tank. So i chopped a bunch of the inner 2" PVC and got all new fittings for the outer 2" PVC and made everything super compact and if it would have worked would have been pretty bitchin. But its not working for some reason.

Now Im thinking of doing Ver. 3 of the overflow; either a dual 3/4" PVC overflow or another single 1" with a slightly different setup.

Now for the question...anyone have any idea of why Ver 2. isnt working? I cant even get a siphon to start and with the pictures you can see the 1" "U" doesnt go all the way to the bottom, preventing water from getting in and i have the vent holes as well, so i have no idea why thing thing isnt working.

Again any help is appreciated
Thanks, Pat

Here is the very first overflow i built, Ver 1:









Heres what it looked like in the tank:









Here is what Ver 2. looks like:









Size comparison, its about 12" from top to bottom:









How deep the inner 1" goes into the outer 2":


----------



## FishFlake (Mar 7, 2010)

I don't see the check valve. Did you install it? Also, are all connections glued?


----------



## Bushpig2 (Nov 29, 2010)

I can fill it without a check valve, so I didn't put one in. I did put one in Ver 1., but again I can fill it without a check valve so it wasn't needed and eventually came unsiliconed from the system. Yes, all the connections were glued together.


----------



## FishFlake (Mar 7, 2010)

My understanding is that the valve is not only for filling and starting, but also for releasing any air that gets trapped over time. When that occurs it can cause the problems your having. Also, I've read that the air is more likely to accumulate at a slow flow rate, whereas at faster rates the bubbles are moved on to the sump. If you do go back to using the valve, you might want to glue it in place first so it's less likely to come undone. You can then silicon if you want to. I hope you get this working, because I've been wanting to make a shorter more compact version too, but have been wondering if it would work. I figured there must be a reason they always seem to be made with that long loop of pipe in the tank. Someone suggested that a certain volume or weight of water is needed for it to work. Not sure though. Maybe you could contact the guy who originally designed these (Wayne Johnson) for help. He's in this link http://www.3reef.com/forums/i-made/nice ... 29396.html. He enters it on page 7 i think as "Aquayne".


----------



## Bushpig2 (Nov 29, 2010)

I think the wate weight idea is the problem. Ver 1. was pretty long and had a ton of "water weight" to fill up and pull the water through the overflow setup. Ver 2. As you can see does not have a lot of lenght or area to do that. Maybe with a smaller diameter pipe it would work, but the 1" seems to be to big of a diamter to sucessfully keep the siphon in such a small distance to achieve the propper Lwater weight" to start and keep the siphon.

Flow rate with the 1" shouldn't have been the problem, from stated above the 1" should do about 600gph, but again I'm pretty sure it comes back to the water weight idea.

All that being said, its kind of a bummer my setup doesn't work as by design and theory it should work, but forces unknown and possible lenght requirements of the pipe I think keep this setup from working.

With my next paycheck (the wife has me on this "saving money for stuff other than my fishtank" plan which is wierd , disturbing and I don't fully understand that either ) ill be designing and testing Ver 3 which will most likely be a dual 3/4" PVC overflow system. Ill post up pictures and whatnot when I get that goin.


----------



## Valous (Jan 30, 2011)

Bushpig2. I am currently building an overflow very similar to this. I did not close my top off I actually left it open and just gluing the 1 inch pipe right against the 2 inch. Once i am done I will try to get pics up. But can i ask how you are filling the overflow up with water with out the check valve and air line?


----------



## Bushpig2 (Nov 29, 2010)

@Valous, you fill the outer 2" pretty much to the top with water, then slide the 1" "U" into the outer 2" and by displacement of the 1", it should fill the siphon tube with the water from the outer 2". Open your ball valve and it should start right up. The only problem i had was that the water that was being displaced wanted to shoot out of the vent holes, so you either need a scond person the first time you try to get it going or get something to plug up the vent holes to keep that from happening.

And id lie to you saying getting this overflow to start like this is easy. Next to none of my overflows actually working right, trying to get this siphon started like this was extremely frustrating and quite messy with water shooting out everywhere and the PVC pipes being a complete P.I.T.A. to get to slide into their correct positions. So with some patience and possibly a helping hand you can get this this up and running provided you dont run into the same problems i had with pipe length and "water weight" and what not.


----------



## Valous (Jan 30, 2011)

well part of your prob might be that air is getting in threw then none glued joints. I know my plan works as this will be the 3rd and 4th that I have helped build. I tested with on a friends tank first. the check valve will take longer to get going for sure. spec since my tank is 24in tall. and the pipe is 2" from the top. Let me see if I can snap some pics right now of it apart. almost all glued and painted.


----------



## Valous (Jan 30, 2011)

here are the picks I still have to drill the small hole and attack the check valves but it will work.

http://i474.photobucket.com/albums/rr10 ... om/001.jpg

close up: http://i474.photobucket.com/albums/rr10 ... om/002.jpg


----------



## Bushpig2 (Nov 29, 2010)

Right on, its lookin good man.

All my joints and connections are glued, i think it was the water weight issue unless someone has any other ideas?


----------



## FishFlake (Mar 7, 2010)

[quote="Valous") I tested with on a friends tank first. .[/quote]


----------



## FishFlake (Mar 7, 2010)

Look on the bright side. When it's a said and done you'll be an expert!

I love trying to figure this stuff out.


----------



## Valous (Jan 30, 2011)

yea the design the guy is using from MFK will work. I had a hard time finding a 2" to 1". so I though why not do this and give a bigger area for my turtles poop to go down. once they get bigger there **** gets big.


----------



## Rhinox (Sep 10, 2009)

> i think it was the water weight issue unless someone has any other ideas?


I first want to say I'm looking at your design #2 and I don't initially see any reason why it shouldn't work.

So, a little about me so you know where I'm coming from - for my job, I'm a mechanical engineer and my company designs and builds fuel pumps. So, I do know a little bit about fluid dynamics, though admittedly not everything. I'm still early in my career.

So that being said, I'm not familiar with a concept of water weight as it relates to s siphon. Water moves through a siphon because the pressure at the inlet of the siphon is greater than the pressure at the outlet. In your case, just so we're clear, the 1" PVC pipe is the siphon tube. The pressure at the inlet is directly dependent on the depth of the water at the inlet. It doesn't matter if that depth of water is in the 2" overflow tube in the tank or not. Similarly, the depth of the water at the siphon outlet determines the the pressure at the outlet. Thats it. The volume of water or weight of the water has no effect.

So I apologize if you know all this already I'm not intending to insult your intelligence or anything. But, in order for a siphon to flow, a pressure difference is required. It takes some amount of pressure to push a fluid through a tube. When you suck soda through a straw, it is the same principle - you are creating less pressure in your mouth so the fluid flows from higher pressure to lower pressure. With your siphon, the difference in pressure is created by a difference in water level. That means during operation, the water level in the tank will need to be greater than the water level in the external 2" pipe the siphon empties into.

I hope you don't mind, but I've marked up one of your pictures to show what I mean:









In the markup, the blue line will be where the tank and over flow level is during power off, when there is no flow going through the siphon. The green, yellow, and red lines are completely made up by me, but represent what needs to happen during operation. The green line may represent 400gpm for example. The level in the external chamber must rise a little bit in order for 400gpm to go down the drain, and the level in the tank must rise as well, in order to push 400gpm through the siphon. The yellow and red lines represent additional flow. Every time you add more flow, the water in the external chamber will rise by some amount, and the water level in the tank has to rise by even more to push more flow through the siphon.

So, with the lesson out of the way, I need to ask another question in order to figure out why its not working. When you start the tank return pump, what happens? I assume the water level in the tank begins to rise. Does any water at all come down the drain?

I can think of a few possibilities for why this is not working. 1: you really aren't getting the siphon primed. Do you have any way to verify there is a siphon before starting the pump? 2: you did not leave yourself enough room for the level of the display to rise before overflowing your tank, and you have to shut the pump off before the flow begins draining to avoid a flood. 3: I see a potential critical flaw in your design - your outlet is too high, and your intank overflow does not really overflow at all. Because of this, you need to add a ton of water to the tank in order to raise the tank level enough to push enough flow through the siphon. I think maybe your sump is draining before the water level in the tank rises enough.

Here is a picture I just made up showing you what I mean about a critical flaw in your design:









Your design is on the left, and the right is the way it is intended to work. So you see the difference is, with your version 2 design, the entire tank water level has to change in order for the siphon to build enough pressure difference to flow. the red lines show the difference in water level, and this is the pressure difference that has to drive your flow through the siphon. If you can't get a big enough difference of water level, the siphon won't flow enough and you can flood the tank - that is, if the sump has enough volume to actually create the rise in the water level of the tank to begin with. The lite blue water is the power off level, and the dark blue is the amount the water levels on both sides need to rise to create flow through the siphon.

The way this type of overflow is intended to work is shown on the right. the tank level stays pretty much constant at the overflow height. It rises just a little bit to facilitate water overflowing into the overflow chamber on the inside of the tank. You can see from the red lines that there can be a much greater difference between the water level in the inside 2" pipe vs. the water level in the outside 2" pipe, allowing the siphon to flow at much greater rates. And this happens without much if any change in the tank water level.

So, for version three what you need to do is lower the output of the drain. The highest level should be the overflow, and this sets the tank water level. You want this at about the level of the plastic trim, maybe a tad lower, so that the tank looks full when the system is running, and you don't see an air gap between the bottom of the trim and the water level. This isn't mandatory, but I think it makes for better looking tanks IMO. The second important level is the level of the drain. The farther below the overflow level you can put it, the more flow you'll be able to get through the siphon. This explains why these overflow units need to be pretty long. Finally, the last important level is the level of the inlet and outlet of the siphon tubes. In both the internal chamber and the external chamber, the bottom of the 1" siphon tube needs to be below the drain pipe. This ensures that the 1" U-tube connecting the 2 sides will never lose siphon with a power outage.

So, I know this was long winded, but by now I think I've convinced myself of the problem - your drain pipe is now too high relative to the weirs you cut on the in-tank side of the contraption. It needs to be low like the first version of your overflow, but you just need to make sure that the siphon tube extends down below the drain.


----------



## Bushpig2 (Nov 29, 2010)

How _dare_ you insult me and my high school diploma with your fancy mechanical engineer job and your sense to point out obvious mistakes! 

Im pretty sure you've nailed the problem on the head. I wasnt even thinking of the outlet being lower than the tank level (Thanks to you) I just mocked up the overflow, and sure enough it was a little bit above the water line.

Unfortunately i can't mod Ver 2 as everything is all glued up. Thats ok though cause i want to build a dual 3/4 overflow that will be a little bit smaller and less intrusive that Ver 2.

Thanks Rhinox!


----------



## FishFlake (Mar 7, 2010)

Rhinox, thanks for taking the time to explain that. That's the explanation I've been looking for, and it's what I suspected. Expressed in a way even fish lovin' knuckleheads like me can understand :thumb:


----------



## Bushpig2 (Nov 29, 2010)

So I went around the "plan" set by the wife and bought all the PVC and all the fittings for the new overflows, except for 2 caps, so ill have to get those tomorrow 8/ But I'm doing 2 3/4" overflows that meet at a 1" "T" that flow into my wet/dry.

Ill post pics up when I have some progression on the whole system.


----------



## Rhinox (Sep 10, 2009)

Bushpig2 said:


> How _dare_ you insult me and my high school diploma with your fancy mechanical engineer job and your sense to point out obvious mistakes!


haha I'm just glad I could help you guys. The mistake wasn't obvious to me right away, I had to talk through it first 

Be careful with doing dual overflows. They can be a little finicky. If you want things to work evenly, you've got to make sure they're as symmetric as possible. Otherwise, one may flow more than the other, or one may not flow at all. The most important part is the in tank overflows - they've got to be at exactly the same height


----------



## Bushpig2 (Nov 29, 2010)

Got it, I was planning on having the 1 1/2" butted right up against the inner lip, tucked up in the inside corner as much as possible. Hopefully this new setup won't be a much as a PITA as the last one


----------



## niktam (Dec 30, 2010)

So not to jump into this thread and hijack it, but I am curious as I am also undertaking a very similiar task, and this thread has helped immensly.

I am hooking up the rubber tube to the venturi ports on my power heads so in theory if the siphon broke during a power outage when power came back it would immediatley re-prime.

Anyways.

I have a mag 9.5, using the 2"-1" sized pipes model would that be too much overflow compared to not enough flow into the tank?

I am thinking I may need to upgrade on my Return pump.


----------



## FishFlake (Mar 7, 2010)

1" vertical pipe (gravity overflow) will give you a max of 600 gph going to your sump.

The mag 9.5 is rated at 950gph, but you need to know it's output at whatever head your setup has and then design your overflow to fit it. The 950gph is for zero head. The mag 9.5 will put out 600 gph at about a head of 8'. So as long as you don't have more than say 7' of head pressure you should be ok. Seems like having more pump than you need is better, then you can turn it's flow rate back if needed to tune your system.


----------



## FishFlake (Mar 7, 2010)

here's an example for you, using the 9.5.

4' of vert. pipe
1' of horiz. pipe
pipe size: .75"
3 90 deg elbows
1 gate valve
1 check valve

head pressure = 7.6

flow rate = 603 gph

maybe more precise than needed, but that should give you an idea.


----------



## Rhinox (Sep 10, 2009)

*niktam*

Actually, you guys are thinking about it backwards. An overflow will only over-flow as much flow as the pump provides. If the overflow is rated for 600gph and the pump only provides 300gph, then only 300gph will go down the overflow.

You should be more worried about your pump being oversized. If your overflow is rated for 600gph and your pump provides 900gph, then 300gph extra is not going down the overflow. Which means 1 of 2 things could happen, either your sump will drain and run dry, or the main tank will fill and overflow.


----------



## fox (Jun 11, 2009)

FishFlake said:


> 1" vertical pipe (gravity overflow) will give you a max of 600 gph going to your sump.


Not true. This is just an avg ball park figure. You can get 900 gph Ã‚Â± thru a 1"ÃƒËœ drain. It really depends on your plumbing techniques.


----------



## niktam (Dec 30, 2010)

Rhinox

Thanks for the reply, thats what I thought, but I wasn't exactly sure.

Anyways, what type paint do these guys use to paint there pvc black?


----------



## FishFlake (Mar 7, 2010)

I don't disagree with you Rhinox. Of course if the pump is under sized, the output of the overflow will be limited to what the pump can put out. If the pump is slightly oversized you can close the valve a bit to match the overflows ability to handle it. What I was saying was that you want to try to match the size of the overflow to the pump. Since you already have a mag 9.5, design the overflow to match it. Which may or may not be 1". It depends on how the system is set up. If you were starting from scratch I'd say first decide how many gph you want, find a pump that gives you that and then size your over flow to fit the pump.

Fox, how would you do that, and can you do it with this type of overflow?

Thanks


----------



## niktam (Dec 30, 2010)

Main reason I asked is I wanted to do TWO overflows, one on each back corner of the tank, as opposed to just 1.

Thanks for the info guys.


----------



## Bushpig2 (Nov 29, 2010)

I used Rustolium(sp?) Plastic paint, I've heard that it comes off after a while, but my spray bar that has been sitting in the tank while I've been fanagling the overflow seems to be doing fine. Its been underwater for about a month now. But I guess the staple black spray paint that is usually used is either the normal Krylon or Krylon plastic paint, you cant get either at home depot unfortunetley, but you can get em at walmart.


----------



## krfhsf (Dec 25, 2008)

This thread is great. Keep it going guys. With lots of pics.


----------



## fox (Jun 11, 2009)

FishFlake said:


> >snip<
> 
> Fox, how would you do that, and can you do it with this type of overflow?
> 
> Thanks


I was just remarking to the statement that 1"ÃƒËœ flows 600gph MAX. I and others have gotten better than that using 1" PVC bulkheads. You can expect to get 600gph out of a 1" gravity fed drain but that is not the MAX flow capable.

Currently one of our tanks gets 1800 gph using two 1" thin wall PVC durso's into 1" bulkheads. We got more thru them but I backed down for piece of mind. They lead directly to 1-1/2" 90Ã‚Â° sweeps, the transition sort of creates a lower pressure and accelerates the volume of flow. Just one of many ways to skin a cat.


----------



## niktam (Dec 30, 2010)

Hey guys, I debated posting a new thread regarding this question but I think in the spirit of how much info is getting jam packed into this thread it would do well to have this all in here.

Following what Little guidance I can get from this thread, and a few other threads that I have found on this forum, especially this thread I am found to have a few questions.

So I started to peice it all together, and got one done, and before I get to the point were I am required to have to go get more replacement parts I figured I would fact check with some pictures.

so here we go.

First is the overall thing, minus the plumbing to go to the actual filter itself, I realize I need to trim the crossbar pipe, and make the intake 1" pipe much longer. Really no question regarding this one seeing as I know whats wrong with this picture.










This is the Exhaust( sure we will call it that!) pipe, notice the hole drilled, I am actually going to make that whole a little bigger so that I can put my plastic tubing in to hook up to my venturi port of my powerheads, Again no questions here.










This is the top of the Intake pipe, And I THINK i did it right, I also included the bottom of the pipe with the cap to illustrate where I am confused that I did it right, if anyone has any insight, or corrections please let me know. Thank you.


----------



## FishFlake (Mar 7, 2010)

niktam said:


> I realize I need to trim the crossbar pipe, and make the intake 1" pipe much longer.
> 
> I also included the bottom of the pipe with the cap to illustrate where I am confused that I did it right


I'm sorry, niktam, I'm not understanding your question about "the bottom of the pipe with the cap"

Your intake needs to be below the tee, but it sounds like that's what you mean by "make the 1" pipe much longer."

Here's an excellent link to this design http://www.monsterfishkeepers.com/forum ... p?t=311243


----------



## niktam (Dec 30, 2010)

Fishflake,

the Bottom of the pipe with the Cap is the bottom of the intake tubeing,

And yeah I realize that I need to make the Intake pipeing longer so that I can lower the actual intake of the system.


----------



## FishFlake (Mar 7, 2010)

Take a look at that link. On the 2nd page he lays out all the pieces and walks you through it. Still not sure what you're asking. Is that last picture the bottom of the intake pipe with the cap off?


----------



## mel_cp6 (Feb 3, 2009)

if you were to replace the outside elbow with a T and use this
T to fill up the overflow/drain then cap it once filled. you may not have to use 
a check valve and it should not lose syphon. obviously you have to use the T sideways.
do you think that would work? im thinking of making one and also thinking of using clear 
pvc or acrylic for the inner pipes to blend it with the tank.

also, how short do you think we can make this work?
good job btw.


----------



## jchild40 (Mar 20, 2010)

cool!


----------



## mel_cp6 (Feb 3, 2009)

nevermind with the clear pvc pipes. its probably going to be hard finding 
all the pipes to fit.


----------



## jeremie (Apr 7, 2011)

[/img]http://www.aquariumlife.net/project...er and and covering it with my diy background


----------



## jeremie (Apr 7, 2011)

[/img]http://www.aquariumlife.net/project...er and and covering it with my diy background


----------



## Rhinox (Sep 10, 2009)

jeremie said:


> http://www.aquariumlife.net/projects/diy-overflow/120.asp
> 
> I had done this over flow like you before but found that a hybrid of the two worked better. I did the compact portion in the viewing area in the tank but adopted this version on the back of the tank. By doing this i was able to eliminate filling the stand pipe and had an advantage if and when i had a clog.
> 
> When I built my new background I was able to completely simplify this by placing a piece of glass in the corner and and covering it with my diy background


In jeremie's blank posts...


----------



## slimbolen99 (Apr 28, 2006)

Here's a you tube vid of how I did mine.
http://www.youtube.com/watch?v=x5riDUpM ... r_embedded

The big difference is that I'm using a water pump to fill the PVC as a means of changing water...not as an overflow into a central system or sump.

Maybe this helps, maybe it doesn't.


----------



## Bushpig2 (Nov 29, 2010)

I think once i get back to cali im gonna do the hybrid of the 2 like Jeremie said. The whole system is kind of a pain lol


----------

