Silent and Failsafe Overflow System

[CJBROWN]

i'm having same issue as you. When i start it up, siphon doesn't start unless i open the ball valve more. When I finish adjusting the ball valve to get it where I want, its almost at a closed position. Are you doing this each time you restart your pump as well? Seems like a hassle.

Yes, and yes. You have to adjust the siphon each time the pump starts. Once done you shouldn't have to mess with it unless you have a power outage or stop the pump. In a power outage it will start back up but will likely not clear itself and you'll have a repeated surge in the overflow that utilizes the secondary 'till you can get to it and clear the siphon line. I have heard some have been able to get their siphon line to clear itself but mine never worked out that way. Since you're throttling it way down so it runs clear, IMO you'll have to fine tune that each startup. I put a mark on the ball valve with a sharpie pen so I can set it back in the same place. It hasn't changed in 3 years!

I put my ball vavle just below the overflow box (external) so it's easy to get to and see the water level in the box. In most installations they recommend the ball or gate valve just over the outlet at the sump. Here's what I have:

 

[andyl9063]

Yes, and yes. You have to adjust the siphon each time the pump starts. Once done you shouldn't have to mess with it unless you have a power outage or stop the pump. In a power outage it will start back up but will likely not clear itself and you'll have a repeated surge in the overflow that utilizes the secondary 'till you can get to it and clear the siphon line. I have heard some have been able to get their siphon line to clear itself but mine never worked out that way. Since you're throttling it way down so it runs clear, IMO you'll have to fine tune that each startup. I put a mark on the ball valve with a sharpie pen so I can set it back in the same place. It hasn't changed in 3 years!

I put my ball vavle just below the overflow box (external) so it's easy to get to and see the water level in the box. In most installations they recommend the ball or gate valve just over the outlet at the sump. Here's what I have:

wow, thanks, i did not know that, thought my setup was defective. i wonder how they were able to get theirs to restart each time. I spent a whole day messing with this. Guess i'll have to pull out sharpie.
I have my ball valve under my tank in the sump where i can adjust it since the tank is back against wall.

 

[Bjanzen]

Well guys..... I have one of both..... One that is set and forget.... Other still is has a trickle. I am learning the differences slowly. I am beginning to think it is a factor of water flow. The first system is about a 10x turnover rate and needs no adjustments. After a pump cycle it makes about 4 large flushing sounds as the open line dumps the overflow and the full siphon gets burped out. It takes about three minutes with no help on my part and off it goes as normal..... No noise... No bubbles at all. The second system I messed up and only have a 2x turnover rate and it just flat won't work. I gave up and ordered a new pump and have it running as a Durso for now. I would be curious to know if my conclusions is similar to what you guys are finding....??

 

[KeithB]

It would seem your siphon isn't fully cleared and and possibly your secondary is too high, can't quiet tell from the top. I have to fully open my ball valve to flush the siphon line, then close it down to where just a trickle comes out the secondary. That way the siphon line has no air in it.

Wait...do I see an airline in the top of your siphon line? Like a durso? That needs to be plugged and all air flushed out.

Nope. No airline. I'll try opening it up and see what happens. Though, with that said, wouldn't and trapped air be removed over time if I'm getting a instant supply of bubbles coming out of te siphon line?

 

[andyl9063]

Well guys..... I have one of both..... One that is set and forget.... Other still is has a trickle. I am learning the differences slowly. I am beginning to think it is a factor of water flow. The first system is about a 10x turnover rate and needs no adjustments. After a pump cycle it makes about 4 large flushing sounds as the open line dumps the overflow and the full siphon gets burped out. It takes about three minutes with no help on my part and off it goes as normal..... No noise... No bubbles at all. The second system I messed up and only have a 2x turnover rate and it just flat won't work. I gave up and ordered a new pump and have it running as a Durso for now. I would be curious to know if my conclusions is similar to what you guys are finding....??

that's what I'm thinking on mine too as well.
Because my pump is rated at 991 gph, but 7 ft head lost is only 408 gph.
So I have to adjust the ball valve to almost close position for it to be silent. When I start up pump again, siphon will not get purge even if I leave it for + 5 minutes. I'll have to open the valve more. If my pump turnover was higher, I wouldn't have to close the valve so much.
Is your second system not working at all?

 

[Cbsailor11]

Not sure if this has been asked before and if so I apologize. Has anyone thought of adding a small pump(ie Aqualifter) to the siphon channel? After a power outage/pump off this would help purge air from the siphon to assist in restarting the siphon. I've seen this used on a hang on overflow.

 

[Bjanzen]

that's what I'm thinking on mine too as well.
Because my pump is rated at 991 gph, but 7 ft head lost is only 408 gph.
So I have to adjust the ball valve to almost close position for it to be silent. When I start up pump again, siphon will not get purge even if I leave it for + 5 minutes. I'll have to open the valve more. If my pump turnover was higher, I wouldn't have to close the valve so much.
Is your second system not working at all?

No..... My new second system is not working silent at all. I have scanned the thread and my system is very close in size to Bean's setup and he tested his down to 300 gph successfully. I am at half that flow rate and probably the problem with the lack of purging ability. The rise in the overflow box is not rapid enough to cause the full siphon line to "burp" the air. My first system will rise rapidly and the second open drain has to go to full siphon function about 4 times before the first gets cleared out and works silently. I hope that helps you guys out..... Just my findings...... Lol

 

[BeanAnimal]

bjanzen,

At 150GPH with 3 standpipes, there is no need for a siphon. The three standpipes will easily run open channel silently at 50GPH each (a trickle). There will be tremendous headroom for safety. Leaning the pipes slightly will allow the water to run down the walls instead of falling through the center and splashing.

 

[BeanAnimal]

Not sure if this has been asked before and if so I apologize. Has anyone thought of adding a small pump(ie Aqualifter) to the siphon channel? After a power outage/pump off this would help purge air from the siphon to assist in restarting the siphon. I've seen this used on a hang on overflow.

If the system is setup properly (thousands are), there is no need for an additional component. Changing the system design to incorporate (or rely on) a mechanical (electro-mechanical) device to function breaks the design criteria and adds a very probable and significant point of failure.

 

[BeanAnimal]

Also, most folks who have "startup" issues have resolved those issues by ensuring that the siphon standpipe is submerged no more than an inch into the sump (normal operating level). A few small holes can be drilled just above the normal operating level if needed. This will prevent airlock in very low flow systems.

The lower the flow, the longer the siphon standpipe will take to fully purge. In some systems this could easily be 15 to 20 minutes.

 

[Dotterer]

Hey Bean,

Wanted to just give a quick THANK YOU to both creating this and still chiming in.

Here's my tank build, underway, that uses your system. It took me 2 weeks to read the thread, but learned so much along the way.

http://www.reefcentral.com/forums/showthread.php?t=2363791

Thank you,

Dotterer

 

[Cbsailor11]

Bean
It is a great system, one I am employing on my current 180 build. My flow will be 900-1000gph based on my skimmer's requirements. My thoughts for the addition would be to assist those with low flow situations to restart the siphon channel. For me personally a 15-20 min purge in unacceptable. You stated that the change would "lead to a probable and significant point of failure", could you elaborate on why you feel this way. I may be overlooking something that is obvious to you.

 

[SGT_York]

With 900 GPH no need to use an aqualifter. Only on really low flow tanks <250 GPH is there any real issue (diameter dependent). An aqualifter presents an additional failpoint with no significant benefit. If anyone is trying to do this with a really low flow 3/4" or 1/2" diameter pipes would be a better route to go than adding an aqualifter.

If plumbed properly there isn't a real startup to increase flow, it should just take a minute for the pipe to fill up with water (purge the air) All the ones I have plumbed start up in 45 seconds or less.

 

[andyl9063]

With 900 GPH no need to use an aqualifter. Only on really low flow tanks <250 GPH is there any real issue (diameter dependent). An aqualifter presents an additional failpoint with no significant benefit. If anyone is trying to do this with a really low flow 3/4" or 1/2" diameter pipes would be a better route to go than adding an aqualifter.

If plumbed properly there isn't a real startup to increase flow, it should just take a minute for the pipe to fill up with water (purge the air) All the ones I have plumbed start up in 45 seconds or less.

yeah, i got it to siphon if i open the siphon channel up, but after adjusting and making it silent. Turn off pump and restart, it will not siphon correctly unless i open the siphon channel more.
Its just a hassle that I don't want to adjust everytime I turn off pump. Are you guys adjusting one time only?
I still can't figure out what's the issue. I got the siphon line running straight down and horizontal into sump (maybe 12 inches).

does the siphon channel have to be open a certain level in order to start siphon? Will it start siphon if its 90% close?

 

[Cbsailor11]

SGT. I'm not looking for my system as I agree 900-1000gph w/ 1.5"IDx36" fall will be fine. I'm looking to assist others like andyl9063 and Bjazen with their issue. Both you and Bean state a failure point, but do not explain as why you feel this way. An assist pump would restart the siphon quicker and negate the need to adjust the valve every time as these two have to do.
Andy9063- I'm not sure but your horizontal run, (I assume you have a 90 as the transition) could be causing a slight back pressure during restarts. Wondering if a change to a 45 at the bottom of the down tube then another 45 for the turn into the sump down line say 6" would help. Just a thought without seeing a pic for clarity. SGT or Bean may have other better ideas.

 

[andyl9063]

SGT. I'm not looking for my system as I agree 900-1000gph w/ 1.5"IDx36" fall will be fine. I'm looking to assist others like andyl9063 and Bjazen with their issue. Both you and Bean state a failure point, but do not explain as why you feel this way. An assist pump would restart the siphon quicker and negate the need to adjust the valve every time as these two have to do.
Andy9063- I'm not sure but your horizontal run, (I assume you have a 90 as the transition) could be causing a slight back pressure during restarts. Wondering if a change to a 45 at the bottom of the down tube then another 45 for the turn into the sump down line say 6" would help. Just a thought without seeing a pic for clarity. SGT or Bean may have other better ideas.

any thoughts on pump? My ball valve on siphon is about 90% close to make it work. If i leave it open on start-up, it starts to siphon in about 30 second, so I'm thinking maybe its the return pump now. If I have stronger pump, I can adjust to where it open more.

 

[BeanAnimal]

Both you and Bean state a failure point, but do not explain as why you feel this way

You are setting the system up to rely on an electro-mechanical device to function properly. All such devices have a 100% probable failure rate over a given time interval. The actual device in question (an aqualifter) has a high probability of failure in a short period of time.

What happens when it fails? How does the system respond?

What is the benefit? The system has been proven to work as designed and reliably on thousands of tanks.

Again, if you are running 250GPH, then there is simply no reason to implement this system, let alone doing so and and then further complicating the setup with a priming pump.

 

[BeanAnimal]

any thoughts on pump? My ball valve on siphon is about 90% close to make it work. If i leave it open on start-up, it starts to siphon in about 30 second, so I'm thinking maybe its the return pump now. If I have stronger pump, I can adjust to where it open more.

You do not have enough flow to purge the air from the standpipe. The discharge is too far submerged in the sump and/or you may need to drill a few small holes in the discharge pipe just above the normal operating waterline in the sump.

 

[andyl9063]

You do not have enough flow to purge the air from the standpipe. The discharge is too far submerged in the sump and/or you may need to drill a few small holes in the discharge pipe just above the normal operating waterline in the sump.

i leave my siphon pipe just right above water, i test it with it 1" under water as well.

When the pump is off, is water suppose to be at the level of the drain pipe or above it 1"?
If drilling a few small holes above the discharge pipe just above the normal operating water line, you mean the water line when the pump is running at optimal level and everything is siphoning quietly and the sound is quiet?

 

[SGT_York]

When the pump is off the level doesn't matter, the holes should be slightly above the water level when the siphon is starting, the idea of the holes is to allow the air to escape.