Silent and Failsafe Overflow System

Floyd, another thing I was thinking about your p-traps with clean out is that you could let air out of the top of the siphon line after you get it first started up and stabilized by just opening the top then screwing it back on. The whole drain would have to be underwater for it to work or the siphon would break, but I could see that being useful to people who aren't using high volumes of water flow. I would bet if you used a clear drain you could see that most of the systems running have some air trapped in the top of the p-trap.
 
Well that fitting only comes in 1.5" and 2", so for a lower flow system you would just use a double elbow as the trap might never clear.

Also I use one without the cap for the siphon, and the one with the cap for the OC.
 
As far as what to name the different variants of overflows, I vote for:

Internal C2C (Original Bean Design)

External C2C (Type used by adova)

Dual Chambered Overflow (Ghost style)

All with a 3 piece drain system of course!

No, we don't need to be coming up with three different variant names to confuse the issue.

References to "as designed" or "per the original design" point to the standpipe/drain line design, not the box that contains them. That design refers to the siphon, open channel, and dry emergency, or as you put it "3 piece drain system." The operation of the system does not change, according to which type overflow box you happen to want to use. It works the same.

There is no need to modify the design according to which box it is going in, unless you are shoving it in a small box, and then it needs to be "herbieized." The current craze over the "ghost overflow" concept, which was originally marketed with a complete BA drain system, being an example of stepping the hobby backwards instead of forward. Back to the RR model of small inefficient toothed overflows, that the Calfo C2C made obsolete.
 
Here is a quick vid - it doesn't sound as loud in the video, but I swear it is, lol.

http://youtu.be/JubuTYv8YaU

Move the valve on the siphon line down by the sump. Baring an air leak, it is cavitation due to the pressure differential across the valve. If you jumped the flow rate up considerably, and opened the valve up, it would probably go away as well. I would pull the valves off the other lines, there is no point to them being there.
 
Everything Floyd said is right on!

One other thing I noticed...
There seems to be some small bubbles being created as water goes over the weir. If these are sucked into the siphon they could be the source of the noise. As the system matures and grows some slime coat the bubbles might go away. Smoothing the weir path would also help.

You should be able to see which drain is getting the bubbles. Might be easier to see w/o the socks. BTW you really only need one sock - on the siphon. It will carry 95% of the flow.

I like Floyd's P trap but you can also use two street ells. If you trim some off the male end of a street ell, it will sit lower in the OF box. That plus a small trim on the slip side of the slip-thread adaptor will lower the siphon if you need to.

And lastly, my pet peeve...
Video doesn't like 'portrait' mode. You just loose lots of visible area. Turn your camera 90 degrees!
End of peeve...
:)

And the winner is... bubbles over the weir!! I shut down the secondary drain completely (just to test) and adjusted the siphon to bring the water level up to just below the weir line. Bubbles stopped and so did the sound. I will repair the weir and see if I can reduce the bubbles - adjust the valves and see how it goes. Oh - and I did reduce the amount of the pipe into the sump.

Question: why do I really need the secondary drain? just protection? Even a little flow in it (with my elbows and such) it ruins the silence for me.
 
Bubbles going down the drain equates to the same effect as an air leak. Anyway, the open channel, or "secondary" as you call it, is so the system self adjusts. It is not required, however, if it is not used, the system will not be a BA system rather be a herbie type, which has some inherent instability to it. It also removes a layer of fail safety.
 
And the winner is... bubbles over the weir!!

Question: why do I really need the secondary drain? just protection? Even a little flow in it (with my elbows and such) it ruins the silence for me.

Nailed it! :dance:

:lol: Nothing like a lucky guess!

Glad you got it figured out. Something is causing turbulence. Like a rock sticking out in a stream. Sand that 'boulder' down and it should get quiet. :thumbsup:

The OC gives you a wide buffer of acceptable flows before you need to adjust the valve. It just gets noisy as the flow increases.

The safety factor comes in with the emergency staying dry. This means stuff won't grow in there and when it's needed it's available.

Herbie drains don't have that third, true emergency.
 
Nailed it! :dance:

:lol: Nothing like a lucky guess!

Glad you got it figured out. Something is causing turbulence. Like a rock sticking out in a stream. Sand that 'boulder' down and it should get quiet. :thumbsup:

The OC gives you a wide buffer of acceptable flows before you need to adjust the valve. It just gets noisy as the flow increases.

The safety factor comes in with the emergency staying dry. This means stuff won't grow in there and when it's needed it's available.

Herbie drains don't have that third, true emergency.

Again, the herbie has the "third, true emergency drain. What it does not have, is the Open channel for self adjustment. Running a siphon without a dry emergency backup is not safe. I don't understand how that is so hard to keep straight...

Herbie: Open top siphon, open top dry emergency. BA: Closed top siphon, closed top open channel, closed top dry emergency.
 
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Anyone know off hand about where in the thread it discusses the conversion of the plumbing of a corner overflow to a herbie style full siphon?
The tank is a 80g drilled in the bottom for a 3/4" and 1" bulkhead with a single corner overflow.
What I am trying to figure out if it is best to make the 3/4" the full siphon or the 1".

Thanks
Tom G
 
Anyone know off hand about where in the thread it discusses the conversion of the plumbing of a corner overflow to a herbie style full siphon?
The tank is a 80g drilled in the bottom for a 3/4" and 1" bulkhead with a single corner overflow.
What I am trying to figure out if it is best to make the 3/4" the full siphon or the 1".

Thanks
Tom G

The Herbie siphon modification is not a part of this discussion, although it is mentioned from time to time. This discussion is about a different drain system designed by BeanAnimal. Do a search for Herbie, and you will be directed to appropriate discussions concerning that drain system.
 
Anyone know off hand about where in the thread it discusses the conversion of the plumbing of a corner overflow to a herbie style full siphon?
The tank is a 80g drilled in the bottom for a 3/4" and 1" bulkhead with a single corner overflow.
What I am trying to figure out if it is best to make the 3/4" the full siphon or the 1".

Thanks
Tom G

Herbie's original thread can be found here. Start there if you're interested in setting up a Herbie system.

The short answer to your question is to make the smaller pipe the siphon and the larger the dry backup.
 
You keep cutting away from the top end where the problem is, but appears to me you are not getting enough head height to fully start the siphon. Consequently, the open channel is taking too much flow. Flow rate vs bulkhead size. The water level should rise in the overflow box up towards the inlet to the dry emergency, if not actually flow in the dry emergency, and then drop. It is not getting there. (I don't know why you extended the upturned elbow; it is not getting up to the upturned elbow where the inlet should be.)

You have a pump capable of driving this 1.5" drain system, but you don't really have the overflow for it, as it is causing problems at the lowest dialed back flow rate (bubbles.) What needs to be done about this, depends on what the flow is going to be when this is running for real. I will say again, that the standpipes are a bit low in the overflow, making for a long waterfall, which if you kick up the flow rate will make you nuts (well along with the teeth as well.)
 
You keep cutting away from the top end where the problem is, but appears to me you are not getting enough head height to fully start the siphon. Consequently, the open channel is taking too much flow. Flow rate vs bulkhead size. The water level should rise in the overflow box up towards the inlet to the dry emergency, if not actually flow in the dry emergency, and then drop. It is not getting there. (I don't know why you extended the upturned elbow; it is not getting up to the upturned elbow where the inlet should be.)

You have a pump capable of driving this 1.5" drain system, but you don't really have the overflow for it, as it is causing problems at the lowest dialed back flow rate (bubbles.) What needs to be done about this, depends on what the flow is going to be when this is running for real. I will say again, that the standpipes are a bit low in the overflow, making for a long waterfall, which if you kick up the flow rate will make you nuts (well along with the teeth as well.)

Thanks,

Ok, i cant do anything about the teeth nor the size of the box or holes drilled for the bulkheads but i do have new bulkheads and this time i bought ABS so it doesn't stand out like a sore thumb in the overflow box. I hope there is no problem with using ABS.

I would really like to get this right this time as i can't really afford to re-plumb this tank over and over :headwallblue:

Before i do anything the way i have it planned is...

(looking at the front of tank into the overflow box)


F/S in the left of the box (All the way to the bottom of the box)

E-pipe in the center (Just a straight ABS pipe

OC in the right of the box (Raised higher to determine working water line)

Also going to remove the ball valve on the OC.

I don't have a set GPH that i need but the system will be housing SPS so i would like to achieve as much as i can get with what i have.
 
No, we don't need to be coming up with three different variant names to confuse the issue.

References to "as designed" or "per the original design" point to the standpipe/drain line design, not the box that contains them. That design refers to the siphon, open channel, and dry emergency, or as you put it "3 piece drain system." The operation of the system does not change, according to which type overflow box you happen to want to use. It works the same.

There is no need to modify the design according to which box it is going in, unless you are shoving it in a small box, and then it needs to be "herbieized." The current craze over the "ghost overflow" concept, which was originally marketed with a complete BA drain system, being an example of stepping the hobby backwards instead of forward. Back to the RR model of small inefficient toothed overflows, that the Calfo C2C made obsolete.

I was making reference to something Floyd said about calling it the "external box, bottom drain variance." He was kinda joking and I was playing along. I do agree that the drain system should work the same on all the difference types of overflows, with only slight differences depending on if the bulkheads exit the tank either horizontally or vertically. I think they did a poor job implementing the ghost. While the concept is a neat idea, the fact that they made it toothed and that they didn't make the internal box near the full length of the tank does hinder its performance in several different areas. But this thread is about the drain system, not overflows in general, so I guess we can leave that for another thread.
 
Hey Uncle,

For my system, how much of a drop do i want inside the overflow box?

If i understand you guys correctly, raising the OC will determine my running water height within the box? doing this i should be able to set the return to 60% as opposed to the 40% its at now. And yes it gets crazy loud as i get into 80%+ on my return!

I should mention that in the video the gate valve is closed quite a bit, not sure how much exactly
 
Hey Uncle,

For my system, how much of a drop do i want inside the overflow box?

If i understand you guys correctly, raising the OC will determine my running water height within the box? doing this i should be able to set the return to 60% as opposed to the 40% its at now. And yes it gets crazy loud as i get into 80%+ on my return!

I should mention that in the video the gate valve is closed quite a bit, not sure how much exactly

Chris,
Nice video! Just to check, in the sump shots, the OC is on the far left with the siphon in the middle, correct?

Could you point me to your sump build? I'm too lazy to look for it! :uhoh3:

Your sump design is going to be loud. There are at least three waterfalls. The sump also seems small for that flow. It comes really close to flooding at the 6 min and 6:27 points in the video. This is NOT GOOD! There's too much of a flow restriction in the back chamber. I fear once you put a skimmer in there it will flood.

There seems to be lots of flow in the OC. Try opening the siphon some till there is almost no flow in the OC.

With all the bubbles from the weir, you'll never get this system really quiet. There will be lots of salt creep too. Lower flow will help this. If you can raise the water level in the OF box there would be fewer bubbles. This would mean raising the three pipes a bit. Perhaps some smoothing work on the teeth would help and it should get a little better when cycled and there is a slime coat on all the surfaces.

Edit:
Oh I almost forgot! What's keeping the return from syphoning at draindown? Is there a check valve in there? CVs are famous for their failure rate, btw. They should be called flood valves on marine tanks.

Hope this helps.
 
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Again, the herbie has the "third, true emergency drain. What it does not have, is the Open channel for self adjustment. Running a siphon without a dry emergency backup is not safe. I don't understand how that is so hard to keep straight...

Herbie: Open top siphon, open top dry emergency. BA: Closed top siphon, closed top open channel, closed top dry emergency.

Full disclosure - I've never run a Herbie. From lots of the comments on RC and some tube vids, it seems like many are running the Herbie with a wet second drain. So this version is a BA-1. Yes, as designed, the Herbie has a dry emergency. It just seems, as implemented, this dry turns into a wet/damp! :eek1:

That's why I went with a BeanAnimal.
 
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