Silent and Failsafe Overflow System

[TheFishMan65]

Do you have a gate or ball valve? Some people say the ball valve can be hard to adjust. Sounds to me like you are having trouble finding the sweet spot. Try letting a little more water than you would like in the open drain and see if the siphon line is silent. Then open the siphon valve just a little, and then wait 10 minutes. Give it time to equalize and see if you can get it adjusted. Hope this helps.

Thought just occurred. How much vertical distance is there between the open drain and the siphon drain. Can you raise the open drain (if they are close to the same height)? I read that the two being too close can cause problems. As a test can you close the valve or block the open drain and let the emergency be the open as a test.

 

[anen]

It is either sucking air via a leak in a fitting, or air bubbles are entering through the intake (via vortex or suspended bubbles from the weir).

Duct tape will not fix the air leak

Are the fitting threaded or solvent weld?
All fittings are slip, I solvent welded everything.

Did you use thread sealant on the caps (preferably PTFE paste, not tape)?
Did not use thread sealant on the caps, but I tightened them extremely tight, and the amount of visible bubbles in the sump coming out of the siphon pipe (steady stream) seams to be way more than could be leaking out of the cap.


How far below the wate line does the siphon pipe terminate in the sump?
Siphon line terminates about 1" under water.

It should only be an inch or so during normal operation.
How far above the siphon intake is the water level in the overflow box? Is it sucking in air?
When I tested with freshwater, at equilibrium it was about half an inch above the siphon elbow. The water level in the overflox box has risen a bit maybe 1.5" since I put saltwater in for some reason.

 

[anen]

I have cepex ball valves, very smooth. Even when I completely shut off the open drain it still makes noise.

For the open drain elbow, I cut about an inch of the bottom of it. I don't think it's a problem of the open drain not allowing the siphon to start, because even when I close the open drain and manually try to start the cycle it still has this choking, sputtering noise.

Do you have a gate or ball valve? Some people say the ball valve can be hard to adjust. Sounds to me like you are having trouble finding the sweet spot. Try letting a little more water than you would like in the open drain and see if the siphon line is silent. Then open the siphon valve just a little, and then wait 10 minutes. Give it time to equalize and see if you can get it adjusted. Hope this helps.

Thought just occurred. How much vertical distance is there between the open drain and the siphon drain. Can you raise the open drain (if they are close to the same height)? I read that the two being too close can cause problems. As a test can you close the valve or block the open drain and let the emergency be the open as a test.

 

[TheFishMan65]

I think you need thread sealant for the caps. Do you have any plumber's tape or putty? I think some said you can use vaseline, but don't quote me on that. It does not take a lot for air to get in. Try switch caps with your emergency one person had a bad cap. Does the emergency go into siphon mode if the others are blocked? And is it silent?

 

[anen]

I have plumbers tape, I will try that when I get home. I didn't think air could get in through a tight cap but I will give it a shot. I have another cap I can try as well. The emergency drains, but it's plumbed to my refugium right now, which doesn't have any water in it, so didn't have a chance to test if that would siphon or not. I will report back!(waiting for the rodi tank to fill haha)

Thanks guys!

 

[BeanAnimal]

I assume (hope) you used threaded caps.

Stop and purchase a tube of white PTFE thread sealant and use that on the caps. It will work much better than the tape. If the caps are solvent weld caps, then the PTFE past may work also.

The caps MUST be sealed. You have air leaking into the siphon and it is causing it to become unstable.

 

[anen]

Where can I buy that stuff Bean?

 

[BeanAnimal]

any hardware, plumbing or bigbox (lowes, home depot, sears, kmart, etc) store.

 

[larryfl1]

hi i am building a 350 tank 96x32x27....

i want to use this method of overflow...

what would be the proper dimensions for the overflow box? also how far down for the box and the bulkheads..?

do you gain much using 1.5" vs 1" ??? i have no issue with 1.5 if it is much better

 

[anen]

That's a big tank.. I can tell you from my own setup, 40 breeder 1" plumbing that 1" was small on the open drain. I can hear a trickle a little bit and I'm only pushing less than 200gph through it. I definitely think you should be going at least 1.5"

You shoudl ahve space to get the elbows out and so that you very little gap between the bottom of the elbows... I don't think bigger matters... you will hardly notice it on a tank that big.

 

[larryfl1]

depending on how much room is needed on the t behind the tank..i can even do 2 " if it makes sense too...

thoughts

 

[anen]

Depends on your flow needs... I think if you follow Bean's design with 1.5s you can achieve 2000gph... How much flow do you plan on running through it

 

[larryfl1]

i would say im looking for 2000-3000 gph...something like that...

 

[anen]

I ran to home depot today as soon as I got out of work grabbed the PTFE sealant and then ran home. This thing is now silent! I am so happy, thanks so much to Bean and everyone else that has contributed to this thread!!! If anyone is on the fence about this overflow, DO IT!

 

[anen]

Yes, you're probably going to want to go bigger. Maybe 1.75"? not really sure, someone with a bigger tank will probably want to chime in

i would say im looking for 2000-3000 gph...something like that...

 

[larryfl1]

is anyone using a reeflo pump with this type of overflow?

i am thinking the dart or barricuda... i need to make sure the overflow will handle it...


Larry

 

[anen]

With the proper piping size it will handle it no problem

 

[larryfl1]

cool...now we need to figure out the proper pipe sizing...any input??

 

[anen]

You can refer to the table in this thread
http://www.reefcentral.com/forums/showthread.php?p=16871218

But depending on the height 2" looks good. Some people have suggested dual siphon pipes, but me personally if I could do it with 1 I would do it with 1...I wouldn't want to tune 4 drain pipes. lol besides if you can only flow 2500 instead of 3000 it's not the end of the world.

 

[larryfl1]

Ok so that is 2 Inch bulkheads?? How much clearance behind the tank do you think will be needed??

How many inches down on tank does bulkhead need to be??

Also dimensions of overflow box? To support 2 inch???