Silent and Failsafe Overflow System
- Thread starter JohnL
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uncleof6
Active member
The air tube needs to be positioned so that if water level rises a bit above "safe", (emergency fully started, and water continues to rise) the tube inlet becomes submerged, and trips the open channel to full siphon, by cutting off the air. (from first page of original thread.) This puts the air inlet above the inlet to the dry emergency. This placement is significant, because if it is too low, the system will not start properly: the open channel robbing the siphon, and not allowing the siphon to purge the air.
For the most part, all starting issues, whether failure or delayed, involve the siphon not fully purging the air, or taking way too long to purge the air as in your case. As I just posted above, there are a finite number of things that can be out of whack, and troubleshooting starts with comparing your system to the model. Chief among causes are: drain outlets too deep in the sump, air leaks, horizontal runs, and the air inlet to the open channel too low in the overflow. If the siphon does start (which evidently it does) we can rule out air leaks. The position (horizontal) or order of the standpipes is irrelevant to the operation of the system, and differing vertical positions really isn't necessary, if the system is setup properly. (i.e. putting the open channel higher than the siphon.)
Relative water levels are an inch or so drop into the overflow, and the overflow water level ~ the top of the down turned elbow on the siphon. It doesn't take a lot of head pressure to start the siphon, around an inch or so in most systems, and usually the dry emergency will kick in during startup (why the placement of the air tube inlet for the open channel is important) so the problem is going to be somewhere else.
How is your system configured compared to the model? The model includes straight drops from the tees, 45° to get under the stand, and straight drop into the sump from the second 45°.
I agree thats why this is so frustrating.
i can rule out depth in sump (.5"), no horizontal runs, but air leaks I can not rule out. the only place i could imagine air leaks is the thread x thread of the connection between the 1" bulkhead and the 1.5'' sanitary t, or the thread x thread bulkhead. all sealed with a good helping of teflon paste.
ill keep troubleshooting.
thanks, -curtis
This is what I thought I read and understood. So this is what I did and this helps me clarify I have it correct. Thank you.
Your last part here with the 45's is where im betting my issues are at. Yes I have some horizontal pipe sections that get under the stand. I will try and reconfigure my Filter socks into a position that I can reroute them with 45's not 90's and have them make a better downward dump.
The only other issue I may have is how far my drain goes into the sump. Whats the recommended amount at the end of the outlet to keep it quiet for water splash?
Everything else I have is exactly like the model in reference other then these two items. This would make sense with the horizontal sections causing it to take longer to purge the air out of those sections more difficult thus the delay. I think ive got close to 6" to 8" down into the sock filter in the first chamber of the sump.
Thank you for the help. Sometimes its the simple things we over look. As well as old habits formed in the past 36 years of doing aquaria that can hang you up. lol Yes this is my first Bean animal overflow. In past Ive had plenty of noisy tanks lol.. :hammer:
Again thanks for the tips and direction. I will make the changes to the horizontal sections. As well as any changes I need to make in the depth into the sump then let you know how it turned out.
i sorta tried that yesterday as i do not have the last about 12 inches of pipe glued together...essentially its 6 inches, a 45, and then another 6 inches into the sump...i will mess with it tonight and get back to ya...
im really wondering if the thread x thread at from the bulkhead to the sanitary T is just not tight enough of a seal...im not sure...
uncleof6
Active member
1" or less below water level...socks are such a pain, and of minimal value to our systems as what we are concerned with in marine systems cannot be removed by mechanical filtration. Mechanical filtration is somewhat of a bad hangover from freshwater systems.
If the last portion of the drain isnt glued you have likely found your air leak. Air can be pulled into the drain anywhere along the siphon line.
with that section removed and just a 6" piece of PVC wedged into the last 45 ending about 4 inches above the water line, i mean wedged all the way in tight, the drain is acting like a stand pipe, both the main drain and the secondary...
Ok Got everthing changed over to 45 degree angles and not 90 degree angles. So now I have zero horizontal runs. Ive got the enda about an in and a half below the water surface. Un fortunatly. Someone borrowed my PVC cement and primer yesterday and used all the cement and left me with an empty can. So tomorrow on the way home I will pick up some more and glue it all together and fire it up and see how it does. Im betting I solved my issues.
As for the sock filters, And being a past salt/reef guy I understand. BUT with Fresh water big high poluting fish such as South and central american Cichlids I need all the mecanical removal I can get. The DIY Sock stands I built are easy to use and easy to chang so they arent to big of a hassle. I have several sets and when a pair get to dirty I just swap them out and run the dirty sets in the Washer machine no detergent but a little bleach and its all clean and ready to go after they air out some. So not a big deal. Plus im running probiotics and other mechanical means of filtration, with weekly water changes. I really prefer to keep the waste levels down. I know I know.. LOL. Not stuff most reef people deal with or like to deal with.
Anyhow if this works out Or not I will let you know. Thank you for the assistance. I do come here alot and read quite a bit of great info you all post.
uncleof6
Active member
OH YEAH! You are a freshwater guy&disregard with apologies. ( I am right LOL it just does not apply to freshwater)
I will say it one more time. Yes I am going to beat a dead horse: Outlets of the drain lines <=1". That is less than or equal to 1". 1" or less, forbids 1.5". 1.5" is too deep. The design calls for 1" or less, requires 1" or less to function properly, so you need to cut the pipes off so they are only 1" or less below the water level in the sump. K have I beat the horse to death yet? :deadhorse:
OK.. Lol I have them 1" Not 3 not 2 and not 1.5" below the water surface. LOL
Horse well beaten and understood!! :thumbsup::deadhorse1:
Ok Uncle.
I'm totally a believer of how it "has" to be. I eliminated the horizontal tubes that were on the primary siphon and the open channel, and yes, there is only 1" below the water surface in the sump. Everything is now at 45 degrees and a very direct dump right into the sump going into the sock filters.
All I can say is say is holy crap! I had the gate valve full open. I have the air tube just in the right spot vs the emergency dry tube. I turned on the switch for the pump and away 1600ish gallons of flow went. The water started over the acrylic overflow and instanly the primary and open channels went full effect. It didn't even go near dry emergency tube. Instantaneous it was loud and in about 6 seconds of turning the knob on the gate valve it went silent. Now I shut it off and turn it back on it starts instantly and goes quiet in 10 to 15 seconds with the flow wide open. I'm positive this set up would handle a lot more. I'm pretty excited to say the least. Thank you so very much for the direction and help. I've got several large tanks I'm setting up that will be done like this.
Question. Does it matter how far spread apart the tubes are from each other? I've got a larger acrylic tank that's already drilled for 2 holes I'd need to add a third. But the 2 already drilled are about 24 to 30 inches apart. Its set up for 2" bulkheads.
Thanks again.
I'm totally a believer of how it "has" to be. I eliminated the horizontal tubes that were on the primary siphon and the open channel, and yes, there is only 1" below the water surface in the sump. Everything is now at 45 degrees and a very direct dump right into the sump going into the sock filters.
All I can say is say is holy crap! I had the gate valve full open. I have the air tube just in the right spot vs the emergency dry tube. I turned on the switch for the pump and away 1600ish gallons of flow went. The water started over the acrylic overflow and instanly the primary and open channels went full effect. It didn't even go near dry emergency tube. Instantaneous it was loud and in about 6 seconds of turning the knob on the gate valve it went silent. Now I shut it off and turn it back on it starts instantly and goes quiet in 10 to 15 seconds with the flow wide open. I'm positive this set up would handle a lot more. I'm pretty excited to say the least. Thank you so very much for the direction and help. I've got several large tanks I'm setting up that will be done like this.
Question. Does it matter how far spread apart the tubes are from each other? I've got a larger acrylic tank that's already drilled for 2 holes I'd need to add a third. But the 2 already drilled are about 24 to 30 inches apart. Its set up for 2" bulkheads.
Thanks again.
Overgrown
Member
Can you elaborate? Would not a deeper box simply cause the waterfall to fall further, creating even more turbulence?
uncleof6
Active member
There are two things that cause problems with overflows:
First is the flow rate is too high for the length of the "weir" or overflow, or from another perspective—the weir is too short for the flow rate. A weir that is too short, causes the head height to rise too high, making for a very turbulent "waterfall," and reduced surface skimming. The longer the weir, the thinner the sheet of water going over, and therefore the less turbulent it will be. Just about all manufactured overflows are too short, and an overflow that runs the full length of the tank, is not too long, yet.
The second issue is the actual height of the drop from the tank water level to the overflow water level. Much more than an inch, and the drop adds to the turbulence, with bubbles etc.
The combination of a very long weir, and a short drop generally solves any issues with turbulence in the over flow, regardless of the over flow depth. The depth really has little to do with it.
We can make it deeper, however, that turbulence will not reach very far down inside the box, and since water is drawn from the "top" of the box, the tubulence and bubbles will get sucked right down the drain, and will have little affect (including no circulation) in the lower depths of the box.
Long, shallow boxes, short drop, and and matched flow rate make for an "engineered" system, that will work better by far, than guess work, and pre-fabbed tanks.
How long? Full length of the back of the tank is ideal. How deep? Deep enough to accomodate the plumbing, with 3/4" or so to spare. If you have a "reef-not-ready" tank (bottom drilled,) you don't have much to work with, and it becomes evident why I advise against buying them.
Overgrown
Member
Just picked up my third custom drilled tank for this overflow (lee mar), and I've gotten them all made for near full lenghth C2C's( just left room for one holes length between the dual returns and sides of tanks )
Your second point however which I've highlighted, clarifies some things for sure. Always learning from this thread, thanks.
Ill stick with more shallow overflows, was just curious about the previously mentioned depth comment and how it relates to micro bubbles.
So just to clarify, as a general rule, if you go deeper in the overflow, you're really just creating a more hypoxic box?
Last edited:
Mark...
Member
I have a question regarding return pump placement and flood prevention. If the return pump is placed high in the sump, say on some sort of platform, (underwater of course), wont this reduce the amount of potential water going into the DT. And if there is a decent reserve space in the DT, maybe even no flooding.
I'm in the research stages and flooding is a big concern.
Thanks...
I'm in the research stages and flooding is a big concern.
Thanks...
GROSSR
Active member
No it won't reduce the chance of a flood. If you don't have a siphon break water will drain down from the display into the sump.
You need to cut the power to the pump and see what happens. The sump will begin to fill without the break. You need to make sure you have enough extra room in the sump to handle anything from the DT. Also, make sure your coast to coast is water tight. My initial attempts, the C2C leaked and drained about 10 additional gallons into the sump. I have since sealed the C2C and I have a siphon break and only about 3 additional gallons go into my sump.
I also have a DIY ATO. The ATO has a low sensor which opens the sensor to add water, plus for the stupid snails, a high sensor which turns off the ATO if the water goes to high. Guess what, the high sensor has activated 2 times preventing my reservoir tank from flooding the sump as well.
You need to cut the power to the pump and see what happens. The sump will begin to fill without the break. You need to make sure you have enough extra room in the sump to handle anything from the DT. Also, make sure your coast to coast is water tight. My initial attempts, the C2C leaked and drained about 10 additional gallons into the sump. I have since sealed the C2C and I have a siphon break and only about 3 additional gallons go into my sump.
I also have a DIY ATO. The ATO has a low sensor which opens the sensor to add water, plus for the stupid snails, a high sensor which turns off the ATO if the water goes to high. Guess what, the high sensor has activated 2 times preventing my reservoir tank from flooding the sump as well.
BeanAnimal
Premium Member
I think his question was with regard to the display flooding...
It is a valid idea, except that limiting the volume available to the return pump means also limiting the volume available to evaporation and/or makes ATO somewhat more complicated. In that spirit, the probability of running the return pump dry is greatly increased, as is sucking in air (via vortex, etc). Carefully planned, the idea is valid. However, the overflow system described in this thread and on my site provides numerous benefits and levels of safety, eliminating the need to engineer a "limited supply" design and the problems associated with it.
It is a valid idea, except that limiting the volume available to the return pump means also limiting the volume available to evaporation and/or makes ATO somewhat more complicated. In that spirit, the probability of running the return pump dry is greatly increased, as is sucking in air (via vortex, etc). Carefully planned, the idea is valid. However, the overflow system described in this thread and on my site provides numerous benefits and levels of safety, eliminating the need to engineer a "limited supply" design and the problems associated with it.
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