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Steve_the_nucks_fan
02-20-2010, 02:49 AM
so i found this diy overflow system online and wanting some feed back. if you have used it or know anything about it please let me know.
also i need to know what size pvc to use.
i have a 96g tank and thinking of running a 30g sump.

sphelps
02-20-2010, 02:53 AM
Yes it works, I did one a few years back. Setup two of the pipes systems in one box and used 3/4". The tank was a 90 gallon and I believe the return rate was about 600gph. I also used clear pvc pipe so you could see if bubbles were building up.

HTH

Steve_the_nucks_fan
02-20-2010, 03:02 AM
Thanks for the feedback. Helps to know someone has used it with good results. Where did you find clear PVC? My local home depot looks like the only carry white and black. What size sump were you running?

golf nut
02-21-2010, 05:14 AM
so i found this diy overflow system online and wanting some feed back. if you have used it or know anything about it please let me know.
also i need to know what size pvc to use.
i have a 96g tank and thinking of running a 30g sump.

where did you find the pic?

Steve_the_nucks_fan
02-21-2010, 05:19 AM
I found it via google just look up diy PVC overflow and you will find the link to go along with the pic.

golf nut
02-21-2010, 05:48 AM
I found it via google just look up diy PVC overflow and you will find the link to go along with the pic.

I get 720,000 options when do that, I will be dead before I find it, could you possibly narrow it down before I die:)

blainep
02-21-2010, 02:58 PM
I've been considering using a PVC overflow for one of my tanks, from the reading I've done, some people swear by them, some swear at them.

So far, what I've read suggests using inch and a quarter pipe to build the overflow with a fast enough flow rate to sweep small bubbles out of the pipe.

Some people also use an aqualifter pump attached to the pipe going over the edge of the tank to pull out any trapped air.

No first hand experience yet, but I plan to be building/testing one in the coming weeks.

Steve_the_nucks_fan
02-21-2010, 06:09 PM
I'll try but I don't think I saved the link. I found it via google. I'll see if I can find the page in my history but there's a good chance I won't find it lol.

Steve_the_nucks_fan
03-08-2010, 03:39 AM
Ok so I built my overflow but it doesn't keep the water flowing anyone have any ideas why? It is based on the pictured i posted at the begining ofthis thread. I someone could help me out that would be fantastic thanks.

bvlester
03-08-2010, 04:19 AM
I have seen one once, I'll look around and find out what I can.


Took a look here is a link:

http://forums.saltwaterfish.com/vb/showthread.php?p=2401854
http://forums.saltwaterfish.com/vb/showthread.php?t=288154
http://www.aquaticplantcentral.com/forumapc/diy-aquarium-projects/63801-easy-diy-automatic-water-change-system.html
http://www.angelfire.com/ab/rayjay/DIYoverflow.html
http://www.youtube.com/watch?v=kjSLPVoLIs4&feature=related

Willpost more if I like them.
Bill

golf nut
03-08-2010, 04:27 AM
Do you have a pic of what you built, it would be easier to troubleshoot.

Chase31
03-08-2010, 06:39 AM
good article found by another refer its posted not that long ago here http://www.aquaticplantcentral.com/forumapc/diy-aquarium-projects/63801-easy-diy-automatic-water-change-system.html

http://farm3.static.flickr.com/2530/3727475247_8cf005dab5_o.jpg

bvlester
03-08-2010, 06:55 AM
this will not work the way it is you need a hole where it goes over the tank also a check velve there. this design is poor will work with a couple changes. check out the links above thay have a design that works realy well.

Bill

Bloodasp
03-08-2010, 07:01 AM
best guess i could make would be that the air hole is too small. As stated it would be great if you can post a pic of the one you made.

golf nut
03-08-2010, 12:56 PM
Did you Prime it properly?

Bob
03-08-2010, 12:58 PM
i have two overflows ..one with the air flow....one without
I like the one without the best....never had any problems...just use a pump that is rated a little higher

Steve_the_nucks_fan
03-08-2010, 04:22 PM
here are a couple pics of what i built.
for who ever asked if i primed it properly yes i did i filled all the chambers with water. anyways if you can help that would be great thanks everyone..

banditpowdercoat
03-08-2010, 04:27 PM
How are you going to start the siphon on that?

Looks good tho, interested to see how it works

mr.wilson
03-08-2010, 04:51 PM
I think you would need a 1" or 1.5" drain line to make something like this work properly. Yours appears to be 1/2" pipe, thus incapable of draining a significant amount of water. You may also need a gate valve rather than a ball valve for more accurate control.

Something like that should really be built out of clear pipe so you can monitor the accumulation of air bubbles see if it is primed properly. If you are on a budget, you could get away with having just one clear PVC pipe and the rest white.

Steve_the_nucks_fan
03-08-2010, 05:39 PM
the cap on the pipe that goes up comes off nothing is glued together yet.
and its 3/4" pipe not 1/2". and that ball valve was the only one i could find at the hardware store so thats what i went with. so ya i just dont understand why i get the syphon going and then it just stops..

Steve_the_nucks_fan
03-08-2010, 05:45 PM
here is a pic i put in my paint program

mr.wilson
03-08-2010, 05:58 PM
As Sphelps mentioned, he used two 3/4" drains similar to yours to drain about 600 GPH. How much do you intend to run through yours?

While I don't think it's a good way to drain a tank, I've seen all kinds of variations of what you are doing, so let's go ahead and trouble shoot it so you can decide if it works for your application.

1) Attach a hose to the intake in the tank and run water through your drain for a minute to assure that all of the air is purged out of the pipes.
2) Run it with a modest pump (500 GPH) and let us know what happens.
- does the tank water level rise over the intake/overflow the tank?
- does the drain quickly siphon for a minute or two and shut down?
- does the drain make a toilet flush sound?
3) Play around with the valve, starting with almost completely closed and slowly work it open until you lose siphon.
4) Play around with the return pump and slowly increase the pressure/volume until the siphon can't keep up.
5) After you get it "tuned" to operate properly, do a simulated power outage and make sure it starts up on its own.

Are you using this with an overflow box for surface skimming? If not, you aren't getting efficient skimming and you will need a strainer to keep critters out.

Do you have a fail safe system if a snail clogs the pipe? Where does all that water in your sump go in the event of pump/power failure or pipe blockage?

Sometimes a cheap overflow ain't so cheap :)

Fishward
03-08-2010, 06:38 PM
I would say that the length of your pipe is too long after the siphon. the velocity of the water shooting down there is going to put alot of pressure on your intake, and with un-sealed joints, may be pulling in air. +1 to closing your valve 90% and trying again with a slower column of water in the pipe. Once you seal it up, you should be able to crank it open more.

banditpowdercoat
03-08-2010, 06:42 PM
Does the line in the tank suck any air at all?? If it gets any accumulated air in the over the top piece, it will loose siphon

golf nut
03-08-2010, 07:06 PM
did you prime by pouring? or prime by suction?

Steve_the_nucks_fan
03-08-2010, 07:13 PM
Ok well I don't want to run a pump for my overflow.
The pipe going down to my sump needs to be that long or it won't reach.
I primed it by filleing it with water and with suction niether worked.
It doesn't make any sense every other overflow I've seen on you tube works mint and for some reason mying won't. I'm just so confused this is my first overflow and I did it because I heard it was easy. Which it's not turnin out to be that way. Lol.

banditpowdercoat
03-08-2010, 07:23 PM
Can you get a siphon started at all? If you can, and it fizzles out after a bit, then chances are it's sucking air somewhere in the siphon loop. Either from the tank inlet, or the pipe connections. If the vent hole is not large enough, it may pull so hard it pulls a vortex in the tank end and sucks air that way?

Steve_the_nucks_fan
03-08-2010, 08:04 PM
i think it might be getting some air from the connections cause its not glued yet. but i finally got it to flow some water. i'm going to post a video on you tude and add the link to this page then everyone can see my issue. should have it up in the next ten mins or so stay tuned.

Steve_the_nucks_fan
03-08-2010, 08:14 PM
ok here is the link to my you tube video.

www.youtube.com/watch?v=hHeLRBUxwZc (http://www.youtube.com/watch?v=hHeLRBUxwZc)

banditpowdercoat
03-08-2010, 08:33 PM
Your vent hole is not large enouggh, Steve. The water level should only go down to the level of the pipe that your vent hole is in, Should never uncover the inlet like that. If the inlet sucks air, you will loose the siphon like how you are. keep increasing the vent hole bit by bit untill you find the diameter that works well.

It's hard to tell, but do you even have a vent just before the last 90 and the down pipe.

Steve_the_nucks_fan
03-08-2010, 08:40 PM
umm ok i'm kinda confuzed on what you mean by vent hole.. lol

banditpowdercoat
03-08-2010, 08:45 PM
OK, refer back to the pic posted earlier in this thread.

http://farm3.static.flickr.com/2530/3727475247_8cf005dab5_o.jpg

See the vent hole shown? this is for a siphon break. It lets air in and when the level of the tank drops below this, it lets more air in, causing the siphon i the downpipe to be lost BUT it keeps the water in the overflow pipe over the side of the tank, so when tank level rises above this vent hole level, the drain will automatically start

Without it, the overflow will completely drain the tank to the intake level, where it sucks in air, just like your Youtube vid does. Start with a 1/8" diameter hole and see how it works, if still same, try 3/16" What some people do is put a piece of airline in there and a John Guest valve, and can vary the valve depending on drain requirements. But fiddlin with drillbit holes will work good too

Steve_the_nucks_fan
03-08-2010, 09:08 PM
ok here is another picture to see if i understand what your saying.

banditpowdercoat
03-08-2010, 09:18 PM
Can't read anything on the pic, to small, but the sideways T that goes into the 90 that does on the downpipe to the sump. Between the T and the 90, drill a hole on the top of the pipe. 1/8" to start. this is a siphon break. I have never made a overflow like you have there, but I know you need an air inlet. Acctually, looking at that Drill the hole in the cap that you filled the pipe up with.


Try it first Without the cap on the top of the T, I bet it just may work fine without that cap, Fill it up, and then open valve and see

Steve_the_nucks_fan
03-08-2010, 09:23 PM
Ok I will try with out the cap and see what happens and then go from there. Thanks so much for all the help.

banditpowdercoat
03-08-2010, 09:28 PM
No problem, I know it may sound strange, drilling a hole in somehting that's draining water, but sometimes they drain water TOO well LOL. need some air to slow them down and equalioze things :D

Let us know how it works. It may be noisy with no cap, so thats why you vary the size of a hole in it, to allow just enough air, but not get that toilet sucking noise

golf nut
03-08-2010, 09:42 PM
I suspect you are not priming at all, I don't care how you force water in the bubbles have the capacity to remain in the top of the U, drill and tap and install a john guest fitting in the first u tube, fill as normal then draw the remaining air out of the top of the U then submerse the JG tube below the surface of the water and you should be good to go, the principle on this system is sound.

Steve_the_nucks_fan
03-08-2010, 09:57 PM
ok well i tried with out the cap and nothing drained out at all.
and yes i am priming it,im puting the garden hose in the pipe. check out the video i posted. i also moved the t joint down so it was lower than the water intake and that did nothing.
do you think it might be because the pipe isnt glued together? and its drawing in air at each fitting? there are just so many variables unvolved in this lol and ive never made one before so i dont know how to trouble shot the problem..

banditpowdercoat
03-08-2010, 09:57 PM
Ya Paul, your right, with a vent hole, it may need a fill hole at the "over the tank" section. When he filled it in the video, with no hole, it got a full suction, and because there was no vent to break suction when tank got to level, it continued to siphon untill the inlet got uncovered and broke the siphon that way.

Steve, it may not start with the cap removed like I suggested because there will not be water in the over the tank bend to start with. This needs to be full and no air in it in order to create the siphon from the tank. Then, the air inlet at the T, that makes it so the siphon will stop, when tank reaches that level, but the over the tank pipe remains full of water

I hope I'm not confusing you, I can see it clearly in my head but seeing and describing are 2 different animals LOL

banditpowdercoat
03-08-2010, 10:06 PM
OK, With my awesome paint skills, I revised a couple changes.

And ya it won't start without the cap. If you filled it, put cap on, started siphon, let run a little to ensure all air out of the over the tank pipe, then pull cap off I bet it may work.

golf nut
03-08-2010, 10:17 PM
and yes i am priming it,im puting the garden hose in the pipe. .

Please believe me, this is not priming it, you may think it is but it isn't,

Steve_the_nucks_fan
03-08-2010, 10:29 PM
lol your paint skills are has good as mying lol.
ok i will try that just means i need to go buy another t and cap.
but i even tried building it just like this video and still didnt work.
http://www.youtube.com/watch?v=kjSLPVoLIs4
let m eknow your thoughts thanks.

Steve_the_nucks_fan
03-08-2010, 10:30 PM
ok so then how do you prime it? oh might primer lol

banditpowdercoat
03-08-2010, 10:39 PM
OK, Thats a good method of priming. They are using a vacuum pump to remove all the air, but there is a check valve in the line so no air can flow back into the system there.

BUT, what he had there still will drain down untill the inlet becomes uncovered. It will not restart after that.

Try what I said with getting the siphon going with cap installed on your T. Then after 15 seconds, remove cap.

And I just remembered, If you put another T in where I drew, your going to have to plug both the inlet and the outlet to the sump in order to prime it. Might be just better to do the remove cap method. Priming and making sure there is no air in the line will be difficult

Steve_the_nucks_fan
03-08-2010, 10:51 PM
Man this getting difficult lol. I thought this was going to be easy. This just seems to be getting harder and harder by every min. So I don't know what I'm going to do.

golf nut
03-08-2010, 10:54 PM
ok so then how do you prime it? oh might primer lol
You have to draw the air out of the highest point.

Bloodasp
03-08-2010, 10:56 PM
It's part of the learning process. The whole concept is hard to grasp when you haven't done it before. By the time you get that working you'll wonder why you didn't figure that out to begin with, which by that time you will never need to make another one ever.

banditpowdercoat
03-08-2010, 11:05 PM
Sit down, relax. It'll be alright. I know my ramblings have probibally confused you more than I may have helped. It is a gift I have LOL.

Lets look at this systematically.

IN the youtube vid, what you had there worked. BUT, it worked to well in the fact that it lowered the bucket level to much. You did have a siphon there. So, how you started it was good.

But, what is needed is someting to slow and lessen the siphon effect when the tank level gets to the T level. That will be the air hole in the cap.

You need to plug the cap to get water to start flowing over the tank portion of the pipe. When you filled the pipe and tried with the cap off, it just drained the sump line and the T up to the cap. Why? because the cap was off and allowing air in, it was not pulling water from the tank, over the top and down

Now, if we cap it, get the water flowing over the top and down, that water in that line, will remain in there if no air is allowd to enter in the upper U. Once water is flowing and you know its spiphoning from tank, uncap the T. This will let air in and release the siphon that Sump line has. You want the water in the sump line to not be under siphon. The only part that needs to be air tight is the over the tank piping.

Uncapping the T should now let the drain slow down when the water level in bucket/tank gets to the level of the T and stop draining. Add more water to bucket, drain should start again.

If the over the tank pipe is sucking air through the joints, the drain will not restart. You need to make sure that section atleast is air tight!

Steve_the_nucks_fan
03-08-2010, 11:29 PM
Ya I think that the joints are letting air in but I don't want to glue everything together and the have to change things around and not be able to know whY I mean. And I think I understand what your saying. I think I'm going to take a break from the overflow for a day or so and then try again. Thanks for all the help dude i think it will go along way when my mind is fuctioning again lol.

banditpowdercoat
03-08-2010, 11:38 PM
Ya I hear ya. Just glue the over the tank part, up to your present T. Nice thing about PVC is it's real cheap stuff to experiment with so not a great expense. But I think if you glue the overflow part, that will be fine and won't need changing.

Steve_the_nucks_fan
03-09-2010, 04:42 AM
Ok so I tried again. This time I glued up to the t pArt lower the t abit and also lowered the intake. I filled up the bucket and also filled the overflow system I got the siphon going and it was working great. Then I pulled off the cap and still had water movment. Then I waited till the water got down to the level of the t and the water slowed. So I then filled the bucket back up and it seemed to still be flowing but at a very slow rate. And I'm not sure why? Lol any ideas? Should that pipe with the cap that come upward off the t be longer? Anyways let me know what you think. Thanks bandit.

banditpowdercoat
03-09-2010, 02:34 PM
Sounds like you got it working :D

When you start the siphon, with the cap on, it flows REALLY fast. But that is what sucks it down and uncovers the inlet. Once you take the cap off, the drain slows to only what is needed to keep the tank/bucket at level. When the tank level rises a bit, more water will be forced through the pipe and down the drain, if tank level lowers, the flow slows. The drain should set itself to flow the same as what your return pump is putting back into your tank. The will ballance and that's what's needed

Glad to hear we have success :D

Steve_the_nucks_fan
03-09-2010, 11:45 PM
ok so i drilled a hole in the top of the cap.. and ive had it sitting in a tub of water with my return pump going for about mmm 4 hours and everything seems to be working fine i can even pull the overflow out of the water and put it back in and it still flows water thanks for all the hekp...

golf nut
03-10-2010, 12:49 AM
i can even pull the overflow out of the water and put it back in and it still flows water thanks for all the hekp...


You mean you can raise the entire unit, and then put it back?

$20 says you can't take it out of the water for 1 minute and put it back and have it still work.

Steve_the_nucks_fan
03-10-2010, 12:57 AM
Umm ya I can so you owe me 20 buck.

golf nut
03-10-2010, 01:00 AM
It isn't possible, when you remove the unit from the water you will lose siphon and it will never return unless you prime the unit again.

mr.wilson
03-10-2010, 01:01 AM
You really have money to burn Paul.

mr.wilson
03-10-2010, 01:07 AM
The whole point of this type of (partial) siphon drain is that it holds water high enough at the gravity drain point, so prime is maintained in the event of a power outage.

The weak link is when air bubbles accumulate at the top of the first bend. This problem is compounded when you can't see what's going on inside the pipes. I would add a 1" vinyl hose at the top, as it fits well over 3/4" hose. I would also install a one way air check valve so you can suck out the accumulated air with a venturi, aqualifter pump, or manually.

golf nut
03-10-2010, 01:08 AM
Tell you what, if it automatically regains a siphon I will send $2000 dollars and have it flown to NASA, they love this stuff .

raising and lowering is easy, taking it out of the water is another issue.

banditpowdercoat
03-10-2010, 01:09 AM
No, I bet he Won't lose siphon he lifts it out. Because he has a J in the inlet there, No air will get into the upper, over the tank pipe so it will remain with water in it. IF the inlet was straight down, with no J on it, then ya all the water will just flow out when you lift it up. :D

Like the Water cooler princeaple.


Paul, you owe him $20 LMAO

Steve_the_nucks_fan
03-10-2010, 01:10 AM
It is possible cause I've done it 2-3 times today. So :p

mr.wilson
03-10-2010, 01:18 AM
Tell you what, if it automatically regains a siphon I will send $2000 dollars and have it flown to NASA, they love this stuff .

raising and lowering is easy, taking it out of the water is another issue.

I'll take the $2000. I think you mean "take the water out of the pipe", not "take the pipe out of the water".

If you lift the pipe out, it will hold siphon because the lowest drain point in the siphon portion is high enough to maintain prime.

Steve_the_nucks_fan
03-10-2010, 01:21 AM
No I took the pipe out of the water. And then put it back in and it worked fine. And that's what you said no way to so you owe me 20 bucks!!

golf nut
03-10-2010, 01:27 AM
Perfect, put it in a box and ship it to me, PM me your Paypal addy and I will be happy to send the money.

should it not work as advertised when received then I will contact you.

Steve_the_nucks_fan
03-10-2010, 01:34 AM
Why would I sent it to you. It's for my tank. And I'm going to be using it.

banditpowdercoat
03-10-2010, 01:35 AM
Paul, why doesn't the water all come pouring out of a water cooler bottle when it's placed on the cooler?? Because the water level in the reservoir is higher than the neck of the bottle and stops air from getting in. Thats how his overflow is working with the upturned hook on the inlet. It doesn't let air into the upper part of the plumbing so the water does not come out.

You of all people should see that.

golf nut
03-10-2010, 01:53 AM
Why would I sent it to you. It's for my tank. And I'm going to be using it.

Because I will send you enough money to build another and still have enough left to have a few beers on me.:)


The original design that you posted isn't quite the same as what you have built, built to the first post what you are describing could not happen,the addition of the U in the tank and the difference in tank to siphon fall off dimension is the reason that you can hold siphon.

the photo in post 17 could or can be deceiving depending on the angle that it is viewed at so I must assume the original pic is what the unit was modeled on, I stand by my word, send me your PayPal addy and I will send you $200, but I do want the actual unit.

Paul

Steve_the_nucks_fan
03-10-2010, 02:06 AM
Ok well I don't have paypal. And are you wanting me to make you one is that what your saying?

golf nut
03-10-2010, 02:16 AM
I don't need you to build me one, I have enough bits and pieces to build dozens of them.

I want that one..

A bet is a bet and I will be happy to send you $200 for that one, even though it isn't made exactly as the original pic it does do what it is supposed to do and a little more.


Paul

PS get a paypal account.

mr.wilson
03-10-2010, 02:23 AM
Ok well I don't have paypal.

I didn't have Paypal until this week. It doesn't seem very secure to me. All someone needs is my email address and guess my password and they can clean out my credit card. I have more security on my cellphone account. Am I missing something?

Steve_the_nucks_fan
03-10-2010, 02:23 AM
Ya well I guess I'll have to get one so you can send me my money. Lol.

golf nut
03-10-2010, 02:36 AM
From your response I have the feeling that you don't believe me, there are many on this board that would be happy to tell you that I am not being facetious, who would you like me to send the money to?

Paul

Chase31
03-10-2010, 02:37 AM
From your response I have the feeling that you don't believe me, there are many on this board that would be happy to tell you that I am not being facetious, who would you like me to send the money to?

Paul

me :D

banditpowdercoat
03-10-2010, 02:40 AM
I've been using Paypal for years. NEver an issue. Best thing to do, if your worried, is set up a separate bank account that you only use for PP. Then, on the highly unlikely chance your acct gets hacked, they don't have access to your real accounts, just whatever money you have transfered into PP

Just chose your pasword well, and change it often if you wish

Steve_the_nucks_fan
03-10-2010, 02:46 AM
Ok so I set up an account what info do I send you?

golf nut
03-10-2010, 02:48 AM
Paging "Coquitlam" anyone in Coquitlam want to send me their email addy so I can send someone their reward?

Paul

golf nut
03-10-2010, 02:52 AM
Ok so I set up an account what info do I send you?
PM me your e-mail address.

mr.wilson
03-10-2010, 02:57 AM
Just chose your pasword well

Can you suggest a good one :)

Steve_the_nucks_fan
03-10-2010, 02:57 AM
i did pm you my email address

Steve_the_nucks_fan
03-10-2010, 03:05 AM
well thank you for keeping your word....

golf nut
03-10-2010, 03:07 AM
You are $200 richer, please pack well , looking forward to another toy.

I will PM you with the shipping information.

golf nut
03-10-2010, 03:11 AM
me :D


Not!!!

Chase31
03-10-2010, 03:17 AM
why would you pay $200 for something that you could easily make yourself or buy for cheaper and i believe it said $2000 in one of your posts

Bloodasp
03-10-2010, 03:30 AM
The thing is even if it looks the same there are some details that might have been in the one he built that makes it work the way it does. Even if he constructs another one similar to the design he might miss that very intricate detail that makes it work or even if it does do what he says.
I don't know if that makes sense but I do think that's why he wants to get what he built and not another one following the blue print.

golf nut
03-10-2010, 03:31 AM
why would you pay $200 for something that you could easily make yourself or buy for cheaper and i believe it said $2000 in one of your posts

It's called integrity, the original design will not hold water, the newer design does, a bet is a bet a skewed bet deserves something and that's my price, did I do something wrong?


Paul

golf nut
03-10-2010, 03:37 AM
The thing is even if it looks the same there are some details that might have been in the one he built that makes it work the way it does. Even if he constructs another one similar to the design he might miss that very intricate detail that makes it work or even if it does do what he says.
I don't know if that makes sense but I do think that's why he wants to get what he built and not another one following the blue print.

He could build them till the cows come home, there isn't anything intrinsic , it is just the changes he made and they will remain constant till the end of time providing the dimensions remain the same..

BlueAbyss
03-10-2010, 04:29 AM
Wow, people build these things all the time, I built one and it works great.

http://forums.saltwaterfish.com/vb/showthread.php?t=288154

It works like the traps on a sink (and like the commercial CPR overflows). I built mine for about 20 bucks, the key is that you need to be able to remove the air from the very top point of the overflow. Once this is done (and water seals each of the bottom curves) when the water level rises on the side inside the tank it will also rise on the side outside the tank. You don't even need that much of a depth for it to work, though longer runs outside the tank seem to increase velocities in my experience... I've seen this design called a 'velocity loop' before, try Googling that :wink:

Acrylic
03-10-2010, 08:55 AM
I wish I had found this a couple of days ago and could have helped you out. I have built a few of these and have one currently setup on my 65G in the basement. It's been running for about 4 months now without failure. I wish the video was still up so that I could see how yours was running.

Steve_the_nucks_fan
03-10-2010, 03:11 PM
I will have a new video up soon of it working the way it should.