Silent and Failsafe Overflow System

2) pass-through bulkheads must be placed such that they are submerged on both sides at all times (usually this means at the lowest point in the box) for reduction of bubbles and silent operation.

Floyd, my only question about this is that wouldn't you want the surface to be a little bit below the top of the bulkhead, so that the proteins on top of the water would still flow to the back to go down the drain. That is why I never really got why people put a durso on their open drain. With both drains running with turn downs, it is always drawing water from below the surface. A straight pipe should be better equipped to skim the proteins that are on top of the water inside the overflow. If you have the system tuned properly, it should only be a very small amount of water going down the open drain anyways. Making it completely silent.
 
Floyd, my only question about this is that wouldn't you want the surface to be a little bit below the top of the bulkhead, so that the proteins on top of the water would still flow to the back to go down the drain. That is why I never really got why people put a durso on their open drain. With both drains running with turn downs, it is always drawing water from below the surface. A straight pipe should be better equipped to skim the proteins that are on top of the water inside the overflow. If you have the system tuned properly, it should only be a very small amount of water going down the open drain anyways. Making it completely silent.

But an open pipe skimming the top would suck in air. You are right, the skimming should be maintained internal to external which means for best performance, the water level should be at the broadest diameter of the hole, meaning the center line. It is hard to obtain perfection, ideally taking just the surface water down to the sump, but we do the best we can everywhere else. By virtue of the thin layer of water over the weir, taking just the surface layer into the OB, we are doing the best we can.
 
Yea, I was gonna say. Then it collects on the surface of the sump. So then our skimmers have to be surface skimming also. If you follow the logic the the end, it gets a little un-obtainable
 
Floyd, my only question about this is that wouldn't you want the surface to be a little bit below the top of the bulkhead, so that the proteins on top of the water would still flow to the back to go down the drain. That is why I never really got why people put a durso on their open drain. With both drains running with turn downs, it is always drawing water from below the surface. A straight pipe should be better equipped to skim the proteins that are on top of the water inside the overflow. If you have the system tuned properly, it should only be a very small amount of water going down the open drain anyways. Making it completely silent.

Unc, he's talking about the pass-through BHs on a in/ex modified

I guess you don't "have" to have them submerged, but it does highly depend on the flow rate. If you are running 3k GPH and 2x 2" PTBHs then if they are not submerged you will tend to get some vortexing and other funky water movement that can cause air to entrain into the water on it's way to the siphon, which loves to decimate air bubbles into pretty microbubbles.

If you are running a lower flow, you can probably get away with lower operating water level. But you also have a water level in your ext box that is related to the siphon and generally having the water level covering the PTBHs also means you are covering the siphon.

Any water than makes it from the tank to the overflow has the surface skimmed. Any water that is now in the overflow system is now subject to a much more volatile level of movement and thus proteins go down the drain. Think about it. How does a protein skimmer even work if it must take the water off the surface in order to remove proteins? It doesn't need to, because these are in the water column, all the time, not just the surface (surface skimming and the skimmer itself are not one and the same) but I may be corrected and am OK with that 'cause I probably explained that wrong.
 
Well that was my next comment. Get enough flow going through your overflow and it will churn the water so much that proteins don't have time to rise to the surface. The more I read and learn from some "old hands," the more I realize that most people aren't running near enough flow through their sump systems.
 
Unc, he's talking about the pass-through BHs on a in/ex modified

I guess you don't "have" to have them submerged, but it does highly depend on the flow rate. If you are running 3k GPH and 2x 2" PTBHs then if they are not submerged you will tend to get some vortexing and other funky water movement that can cause air to entrain into the water on it's way to the siphon, which loves to decimate air bubbles into pretty microbubbles.

If you are running a lower flow, you can probably get away with lower operating water level. But you also have a water level in your ext box that is related to the siphon and generally having the water level covering the PTBHs also means you are covering the siphon.

Any water than makes it from the tank to the overflow has the surface skimmed. Any water that is now in the overflow system is now subject to a much more volatile level of movement and thus proteins go down the drain. Think about it. How does a protein skimmer even work if it must take the water off the surface in order to remove proteins? It doesn't need to, because these are in the water column, all the time, not just the surface (surface skimming and the skimmer itself are not one and the same) but I may be corrected and am OK with that 'cause I probably explained that wrong.

Not quite. The skimmer works based on the CONCENTRATION of dissolved organics, (proteins, vitamins, secondary metabolites, etc.) The higher the concentration the more efficiently the skimmer removes them. So taking the surface layer off the tank in general, you have a higher concentration of dissolved organics by default, as these compounds are hydrophillic (water hating) and rise to the surface of the tank. Thus they will also collect on the surface of the overflow, the surface of the sump, anywhere there is an air/water interface. This basic hydrophillic property is precisely why a skimmer works at all period. Now yes the mixture in the overflow box is "volatile" as you put it. But running water through submerged holes undoes that to a certain degree. Couple that with a horribly inefficient internal box, and you are just accomplishing nothing, but making the setup harder to build.

This "thin" layer equates to very long weirs without teeth. Small toothed internal boxes don't get the job done. That is the whole point to the full width C2C. The passion for "smallest footprint" in the tank is misguided. This is not only about dissolved organics, but surface renewal for gas exchange as well.

I think it is a mistake to have the holes fully submerged, and running through bulkheads, (more restricted communication) as you are leaving behind an organic slick on the internal, (whether it is apparent or not.) I read the logic behind it (turbulence) and i disagree with that as well. I run flow rates others seldom even think about, and I don't have the turbulence problems as I am not cramming things in small boxes (whether internal or external) as some are doing by copying the ghost overflow.

I also think it is a mistake to keep this line of thought alive in this thread, as it is NOT helping folks implement this system, have it work out of the box the first time, and solve the issues they may be having with them. It is simply making the thread more cumbersome, more confusing, with each successive post. Before long this will come back as "I thought that the Bean system was the ghost overflow..." just as it came back as "I thought the Bean system just added a dry emergency to the Herbie..." :)
 
1) This thread is about a Silent and Failsafe Overflow System. i.e. a drain system.

2) You can do this with or without a coast-to-coast weir overflow, that is irrelevant. I won't argue with you about the merits of the true weir and surface skimming but IMO that is not relevant to the overflow system itself, it's just a very good idea to use that.

3) Even though this thread is about a drain system and not the form of the internal overflow box, I'll just say this: Some people want teeth for one reason or another, and that is their choice. Quit harping on people that use teeth because that is their choice and has zero, and I mean zero, impact on how the actual drain system functions. zero.

4) Your point about an internal overflow with pass-through holes being so wrong because the surface organics stick to the surface? What happens when you have a true (post #1) BA drain system and a C2C...you have surface skimming into the overflow box, and then the main siphon drain is a down-turned elbow that is underwater. Not at the surface. Not skimming off the surface. Neither is the open channel. Neither is the emergency, which is always above the water, unless it's engaged. Using your argument that surface organics would build up in the internal box doesn't make any sense because after 2 years of running the tank everyone would have some huge thick layer of organics built up. At some point, a limit will be hit where whatever surface organics there are get busted up and go down the drain just as fast as they build up. If running an external box they might collect a bit better on the surface but it this was a problem you would see pics of nasty external boxes all over the place, but you don't. Same reason. Even if they are...better than building up on the surface of the tank, no harm done in the overflow box. So, who cares, really, if you have organics built up in any overflow box.

5) people want to take advantage of the way this system works on their tank. So if they have a rimmed glass tank and their choice is that they don't want to have a big internal overflow box, that is...their choice. Quit telling people they are wrong because they really aren't. I see no problem with someone doing it differently based on what they have the ability to do. What do you expect people to do, just get rid of their entire tank and have a custom tank built just so they can use the system "as intended"?

So in conclusion, quit telling everyone they are doing it wrong and that they have to do it the "pure" way. Quit pointing out every little difference between someone's setup and the OP setup and how their build shows a complete lack of understanding of the principles of the original design. While there are core principles that definitely need to be understood in order to make the system work, there is definitely more than one way to skin a cat. Community forums are about helping people not about ripping them apart.
 
ugh...open channel standpipe turbulence

ugh...open channel standpipe turbulence

Hi all, I am increasingly frustrated. My BeanAnimal system was working and is now not working. The open channel pipe is very turbulent and I cant seem to adjust my system so that it works. I had elbows and today I took it all apart and reconfigured it so that the pipes are straight and go straight down into the sump. My problem is that the open channel pipe is acting like the syphon and I dont know why this is happening. Ive powered off the system and restarted it and every time, the bulk of the water goes through the open pipe and the flow is sinusoidal, the water rises and falls in the overflow which starts and stops the syphon. please help with advice.....
 
Hi all, I am increasingly frustrated. My BeanAnimal system was working and is now not working. The open channel pipe is very turbulent and I cant seem to adjust my system so that it works. I had elbows and today I took it all apart and reconfigured it so that the pipes are straight and go straight down into the sump. My problem is that the open channel pipe is acting like the syphon and I dont know why this is happening. Ive powered off the system and restarted it and every time, the bulk of the water goes through the open pipe and the flow is sinusoidal, the water rises and falls in the overflow which starts and stops the syphon. please help with advice.....

It is sometimes seen that the system works for a while, and then does not. There does not appear to be a pattern to it, though it does go back to the basic setup of the system.

IF your system is configured as it should be, the reason it is not functioning will be very limited to a short list. Generally, this will be the outlets for the drains too deep in sump, or the air vent line too low in the overflow, which will trip the open channel to siphon before the main siphon purges the air. Both of these things will cause the flow in the open channel to be higher, or be the bulk of the flow and cycling of the open channel.

Pipes should be no deeper than 1" below the water level in the sump, and the inlet to the air vent line should be higher than the inlet to the dry emergency.

One of the issues can be horizontal runs in the drain lines, but you already took care of that, it sounds like.

One of the increasingly common problems is the bulkhead size vs. flow rate. If you are running a low flow rate, on 1.5" bulkheads, that will cause a starting issue, though the symptoms could vary some.

Some of the current variants do not allow enough head height to build to get the siphon started properly, due to undersized external boxes, and the height relationships are changed to get it to fit the box.

FYI, the valve on the siphon being open too far, will not cause the flow in the open channel to be excessive. After converting and running 250+ of these systems, I have never seen that happen. More likely that would be a symptom of the valve being closed too much, or as I said before the air vent line being too low in the overflow.

Default start up siphon valve setting is wide open. After the siphon drops the water level in the overflow, the valve is closed till water just starts to flow in the open channel. If you can't get the siphon to drop the water level, or you can't get the water level to rise, you need to kick the flow rate up. Sometimes these issue are "cured" by going back to step one of the adjustment steps.
 
Thanks for the great info. I appreciate it. I took a few pictures. I also made a video but I dont see where to upload video so I am attaching pictures in sucession.

I experimented and when I remove the air line from the open channel, the level stabalizes but the open channel is still doing all the work and is then a constant turulent waterfall. When I reinsert the air line, the water flushes and fills and flushes over and over.

It did work well since september of last year until recently when I just couldnt adjust it right. Now that I made everything perfectly vertical it acutally got worse.

I think I see a possible problem in my setup, but here it is, and I am open to modifying it:

  • From left to right:
  • Return from sump
  • emergency channel (faced up)
  • open channel (capped with flex hose for air...u shape facing down)
  • full siphon (faced down)

More info:
  • the original 110g tank came with a built in overflow. Predrilled with 4 holes (0.5", 0.75", 0.75", 0.5").
  • I converted one of the original returns to be the full siphon and the larger two in the center were the emergency and open channel.
  • So possibly not an ideal system since the full siphon has smaller diameter. but its what I had to work with.
  • In addition to the full siphon having a smaller diameter, the full siphon U shape is higher by about 1/3 to 1/2 of an inch. this I can remedy if needed.
  • In the sump, the open channel is submerged about 1inch below sump level while the full siphon is submerged 1.5-2.5inches below sump level.

I will post more pics tomorrow.
 

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I experimented and when I remove the air line from the open channel, the level stabalizes but the open channel is still doing all the work and is then a constant turulent waterfall. When I reinsert the air line, the water flushes and fills and flushes over and over.

It did work well since september of last year until recently when I just couldnt adjust it right. Now that I made everything perfectly vertical it acutally got worse.

I think I see a possible problem in my setup, but here it is, and I am open to modifying it:

  • From left to right:
  • Return from sump
  • emergency channel (faced up)
  • open channel (capped with flex hose for air...u shape facing down)
  • full siphon (faced down)

More info:
  • the original 110g tank came with a built in overflow. Predrilled with 4 holes (0.5", 0.75", 0.75", 0.5").
  • I converted one of the original returns to be the full siphon and the larger two in the center were the emergency and open channel.
  • So possibly not an ideal system since the full siphon has smaller diameter. but its what I had to work with.
  • In addition to the full siphon having a smaller diameter, the full siphon U shape is higher by about 1/3 to 1/2 of an inch. this I can remedy if needed.
  • In the sump, the open channel is submerged about 1inch below sump level while the full siphon is submerged 1.5-2.5inches below sump level.

I will post more pics tomorrow.

I am not seeing a dry emergency in the images.

Removing the air vent line should not have such a dramatic effect on the system. I can't really tell from the images where the inlet is in relation to the inlet to the dry emergency, however the inlet to the air vent inlet should be up around the trim lip inside the tank. This keeps it up and out of the way, unless the system is about to flood. It will then trip the open channel to siphon, and drain the box down, preventing the flood.

You need to cut off the siphon pipe in the sump so it is less than 1" deep in the sump. 1.5 - 2.5" is way too deep, and I do not think the system ever worked "quite" right, though it has only recently become more noticeable.

The siphon being one of the smaller bulkheads (I am assuming you are calling out bulkhead sizes) is the way it is supposed to be. With the open channel and dry emergency on the larger bulkheads. This would never be an issue, and would not be a source of problems.

However, the siphon being higher than the open channel will cause you all sorts of problems. This is a little bit difficult to explain, but you need to bring the open channel up, so that the point at which the water heads down in both the siphon and open channel are at the same level. This "weir" is inside the tee where the branch joins the run. When the pipe sizes are all the same, this is easy. When the pipe sizes are different it takes a little more thought to set it up.

You do need to understand the limitations of the set up you have. The maximum theoretical flow capacity of a .5" bulkhead is 416gph with a 24" drop, and 510gph with a 36" drop. That is without pipe attached to the bulkheads. Once pipe is attached, those numbers will drop due to friction loss. You are going to be limited to less than 5x system volume, which is pretty low for a marine system that should be running up around 1K. That said, there is not much you can do about the bulkhead hole sizes.

Barring major custom work on the tank, what I would suggest is you start over. Put a 1" siphon on one of the 3/4" bulkheads, and put a 1" dry emergency on the other 3/4" bulkhead, set up as a proper "Herbie." Plug the .5" holes with capped bulkheads. Run the return line up over the back. This would be for the benefit of the system, and would up your flow capacity to a more acceptable level, for the tank size/dimensions. BA's system is the better of the two, but circumstances sometimes change the playing field.
 
I totally got that wrong and am not sure how to measure the bulkheads. Possibly, the two in the middle are 1.25" bulkheads and the two on the ends are 0.75" bulkheads. the in-overflow PVC pipes are 1.25" PVC (interior) and 0.75" PVC (outer) and in sump PVC is 1" (inner) and 0.75" (outer).

Also, kind of relevant:) is that I found 3 snails in the Full siphon!!! One in the PVC and two in the valve. Pic attached of the PVC 'plug'. At least I know I wasnt going crazy in not getting it to work.
 

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I totally got that wrong and am not sure how to measure the bulkheads. Possibly, the two in the middle are 1.25" bulkheads and the two on the ends are 0.75" bulkheads. the in-overflow PVC pipes are 1.25" PVC (interior) and 0.75" PVC (outer) and in sump PVC is 1" (inner) and 0.75" (outer).

Also, kind of relevant:) is that I found 3 snails in the Full siphon!!! One in the PVC and two in the valve. Pic attached of the PVC 'plug'. At least I know I wasnt going crazy in not getting it to work.

Well that would certainly make the thing not work. You can probably disregard most of the forgoing, except the height relationship between the siphon and the open channel, and the depth of the pipes in the sump, and the placement of the air vent inlet. These things do affect the performance of the system, and it is relatively simple to make sure they are right.

What I am wondering is why the dry emergency did not take the bulk of the flow, rather than the open channel. That is what is supposed to happen in case of a blockage of the main siphon. The open channel is the last resort fail safe. The dry emergency taking flow would make noise and alert you to a problem, much the same as the open channel. So I am thinking there is a setup "error" with the system.

You can measure the bulkhead size by the size of the pipe that fits in the bulkhead. They are not named for the hole size they go in, rather the PVC pipe size. I would up size all the pipe to at least 1", and keep the pipe size the same, inside the box and going down to the sump, for each drain line.

One thing you do know, is the safety systems work.
 
What I am wondering is why the dry emergency did not take the bulk of the flow, rather than the open channel. That is what is supposed to happen in case of a blockage of the main siphon. The open channel is the last resort fail safe. The dry emergency taking flow would make noise and alert you to a problem, much the same as the open channel. So I am thinking there is a setup "error" with the system.

SAZ03 said that the problem did not persist when the airline was removed from the OC. Therefore, my guess was that the water level was rising enough to plug the airline on the OC (since the primary siphon as blocked) and start the siphon there. I would suspect that the airline was not above the emergency drain and the OC siphon took affect before the emergency had a chance to kick in...
 
All put together and working. And since I had it apart I leveled everything out and now it's calm and quiet. I guess I need to devise a way to keep out the snails; I found my next project.
 
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