Silent and Failsafe Overflow System

[BS87]

Originally Posted by uncleof6

3/4" is too small for practical applications for marine systems. It plugs up far too easily, and the friction losses are extreme. The minimum bulkhead/pipe sizes for marine systems should be 1". The only exception would be pico tanks, and there would be no sense in going through all of this.

You will have a heck of a time getting a 3/4" open channel silent, which the silent flow capacity is ~ 25gph give or take. It is way smaller than the minimum practical durso, which is 1.25" pipe on a 1" bulkhead.

By marine systems, do you mean strictly saltwater or do you mean aquariums in general? He mentioned it was for a freshwater tank, I'm not informed enough about the subject to know if there a difference.

[Ironwood]

Hi, I currently have a 72 gallon bow front with a 20 gallon sump underneath the DT. I have a 3/4 internal weir and an external overflow that has the beananimal system. All of the piping is 1.5". I'm thinking of putting a 40 gallon sump in the basement to free up space in my cabinet. My question is could I reduce the piping just before it enters the wall to be 1" instead of 1.5". On the main stand pipe I would reduce the pipe to 1" after the ball valve.
I just think the 1.5" is overkill for my setup. I'm also thinking that since the water will be falling ~5' the larger pipe would cause more noise. Thanks

[pdiehm]

Starting to hear some noise from the open channel pipe, does that mean too much water is flowing down that pipe? Distance down is about 4'

[woodnaquanut]

Originally Posted by pdiehm

Starting to hear some noise from the open channel pipe, does that mean too much water is flowing down that pipe? Distance down is about 4'

That's what I'd look at first. Is the siphon wide open? If not, try giving it a tiny nudge open and see what happens with the OC.

Another thing to check is if you have a strainer on the siphon, perhaps it needs a cleaning.

[sleepydoc]

Originally Posted by BS87

By marine systems, do you mean strictly saltwater or do you mean aquariums in general? He mentioned it was for a freshwater tank, I'm not informed enough about the subject to know if there a difference.

Aquariums in general. A ¾" siphon may handle the flow just fine, but a3/4" open channel can barely handle any flow before it starts to make noise.

[sleepydoc]

Originally Posted by Ironwood

Hi, I currently have a 72 gallon bow front with a 20 gallon sump underneath the DT. I have a 3/4 internal weir and an external overflow that has the beananimal system. All of the piping is 1.5". I'm thinking of putting a 40 gallon sump in the basement to free up space in my cabinet. My question is could I reduce the piping just before it enters the wall to be 1" instead of 1.5". On the main stand pipe I would reduce the pipe to 1" after the ball valve.

I just think the 1.5" is overkill for my setup. I'm also thinking that since the water will be falling ~5' the larger pipe would cause more noise. Thanks

How much flow are you aiming for? You may be able to do that without an issue. The main problem will likely be the open channel pipe.

I don't have experience with basement bean setups, but you may need to put the valve on the siphon line in the basement. Not sure if it would have trouble purging air with a long drop after the valve

[uncleof6]

Originally Posted by BS87

By marine systems, do you mean strictly saltwater or do you mean aquariums in general? He mentioned it was for a freshwater tank, I'm not informed enough about the subject to know if there a difference.

By marine systems I mean marine systems. If he is doing a freshwater system, then that is a bit different. Freshwater piping is less likely to become occluded, and the flow rates are less critical.

As for differences between Fresh and Marine systems, the fluid dynamics are the same, everything else is different.

[Ironwood]

Originally Posted by sleepydoc

How much flow are you aiming for? You may be able to do that without an issue. The main problem will likely be the open channel pipe.

I don't have experience with basement bean setups, but you may need to put the valve on the siphon line in the basement. Not sure if it would have trouble purging air with a long drop after the valve

Sorry for the delay. The max would be 1100 but more realistically 900. I think your right about the ball value especially to make it silent. It could be a pain to adjust the first time though. I plan on using ultra flex pvc so there won't be any sharp turns. Thanks

[Shawn O]

Hi uncleof6, I just bought a 55 gallon setup and want to ditch from the HOB overflow in favor of drilling the back and using a BA system. Planning on using a glass overflow box on the outside and a narrow weir box on the inside. Do you think 3/4 for all three pipes is large enough or should I go with 1" on all three? 1" just seems to me like overkill on a 55. Your thoughts?

[sleepydoc]

Originally Posted by Shawn O

Hi uncleof6, I just bought a 55 gallon setup and want to ditch from the HOB overflow in favor of drilling the back and using a BA system. Planning on using a glass overflow box on the outside and a narrow weir box on the inside. Do you think 3/4 for all three pipes is large enough or should I go with 1" on all three? 1" just seems to me like overkill on a 55. Your thoughts?

how much flow were you aiming for? Depending on your flow, ¾" for the siphon may be enough. For the open channel pipe, it's pretty useless, though, as it can't really handle much flow without getting noisy. You can drill for ¾" bulkheads and then upsize the pipe, however. The other problem with ¾" pipe is it's very easy for snails and other stuff to occlude it completely.

If you're planning on an external overflow box, acrylic may be better. You have to keep the holes at least 1 diameter from the edges to keep it from being too unstable. Even a ¾" bulkhead requites at least a 1 ⅜" hole, meaning your box needs to be at least 4.25" wide.

[805reef]

Originally Posted by uncleof6

1' Bulkheads. As it looks to me, you won't break 1200gph regardless. No point in using bulkheads that can flow 3000gph. 1" bulkheads will get you to 2000gph anyway, with a little over a 3' drop.

That said, with a 300 gallon tank, you are going after a elephant with a pea shooter for a pump, and you should be targeting 3000gph, rather than playing around at 1200gph. In that case you would want to use 1.5" bulkheads.

IF you insist on using the pea shooter, you will HAVE to increase the inlet pipe size to 1.5" if you are running external, and running a 1.5" return line. 2" inlet would be better.

I've been thinking about your comments a lot and researching and I have decided to go with a super dart gold which should get me around 3000gph. So I will go with 1.5" plumbing.

I also decided to do an internal coast to coast (peninsula so 36") instead of an external. Now I just need to work out the dimensions of the box.

Thanks for your input uncle!

[Rustyprop]

Thanks for the ideas

[Shawn O]

Originally Posted by Shawn O

Hi uncleof6, I just bought a 55 gallon setup and want to ditch from the HOB overflow in favor of drilling the back and using a BA system. Planning on using a glass overflow box on the outside and a narrow weir box on the inside. Do you think 3/4 for all three pipes is large enough or should I go with 1" on all three? 1" just seems to me like overkill on a 55. Your thoughts?

Originally Posted by sleepydoc

how much flow were you aiming for? Depending on your flow, ¾" for the siphon may be enough. For the open channel pipe, it's pretty useless, though, as it can't really handle much flow without getting noisy. You can drill for ¾" bulkheads and then upsize the pipe, however. The other problem with ¾" pipe is it's very easy for snails and other stuff to occlude it completely.

If you're planning on an external overflow box, acrylic may be better. You have to keep the holes at least 1 diameter from the edges to keep it from being too unstable. Even a ¾" bulkhead requites at least a 1 ⅜" hole, meaning your box needs to be at least 4.25" wide.

If flow should be 10x system volume, and I plan to start out with a 20gal sump to start (moving up to a 30 at some point), should it be around 800 gph? As you stated, if 1" open pipe is minimum and 3/4" siphon will do about 750 gph, I'd probably want 1" siphon w/ball valve to restrict, correct? I have two small PHs in the tank so I'm thinking somewhere around 500~600GPH should be acceptable for the drain/return system? Do you thing a 5" wide overflow box would accommodate 1" pipes?

Thank you, sleepydoc, your help is much appreciated.

[BlackShark087]

Hello,

I run over the thread but I didn't found the answer.

Here is my setup :

http://reefcentral.com/forums/showthread.php?t=2496991

265G Marineland CornerFlow + 125G sump

I have 4X 1" Holes.

I found that other members had issue with the Cornerflow grid making waterflow restriction if the chose the option of one side siphon.

There is also people who had issue of waterfall inside the cornerflow

I also found issue with balancing the siphon from the 2 side can be painfull. (Herbie)

For me the most important is that the system is silent as much possible with the less adjustment and the max flow rate. (yes I want everything)

So here Is my plan :

height of them Rate From ---0+++ / the corner flow grid water level as the 0 / the Factory length of the durso

| Open channel standpipe / Durso 0 | Full Siphon standpipe ---0 | -> Straight to the sump

| Open channel standpipe / Durso -0 | Emergency standpipe 0+ | 2X 45 deg angle run back to the sump

Tank over filling 0+++

Ill Upgrade all the stand pipe to be the same size 1" 1/2 down reducer to 1" bulkhead
4 straight pipe to sump with 3 gate valve

Ill Cover the Cornerflow with a peace of acrylic I dont want anything there, no light, no algua, no nothing.

for Return Ill Run a 1"1/2 pipe up from the side of the tank and build a manifold with 3X 1" return from the top of the tank those 3 gonna split in 2 for a total of 6 water return. Anyway my opinion is that 2 return is not enough. I want to max up the water flow.

My logic behind only 1 Full syphon is to get a pump have a 1" output but with a very High flow rate that im gonna reduce with a gate valve for adjustment to match the exact flow of 1" full siphon with no restriction. so instead of adjusting the overflow Ill adjust the return of water that goes in the tank.

The last thing in consideration is do I go with 2X Open channel standpipe or 2X Emergency standpipe for more safety. Cause im gonna max up the flow for the manifold.

And finally I need to know the flow rate a my full siphon to buy a pump that is going to overrate it. (Ill post back with the specific details about length, height for now is more a concept....

Thanks for you help and bring me all your suggestions.

[jc03]

Hi everyone, I'm sure this has been answered about a million times in the thread but I didn't see it jump out when I searched it. What is the ideal water level in my overflow box? Meaning, how far a drop should I have over the bottom of the weir? Is there an ideal level on the bulkhead as far as height? Thanks.

[BeanAnimal]

If the bulkheads exit the back of the tank (as opposed to the bottom of an external overflow box) the water level will usually end up near the top side of the down turned elbows. The drop from the weir edge to this height will depend on the placement of the bulkheads (which also help dictate the overall depth of the overflow box). You want some headroom there, but the larger the drop, the more chance of waterfall noise you have. Make sense?

On most tanks setup following the published plans and using the 1.5x or 2x diameter from the trim for bulkheads and a weir at the bottom edge of the trim, this leaves a distance between the weir edge and overflow level of an inch or two (depending on flow rate, weir width, box width, etc.)

Follow the general design criteria and you will be fine:

• Center of bulkheads at least 2x the drill diameter from the top edge of the tank.
• Top of weir at bottom edge of trim
• box depth (front to back) enough to get your hands into and fit elbows on bulkheads
• box height (bottom of box) enough to accommodate the down turned elbows with maybe 1/4" to 1/2" clearance, again depending on desired flow.

Uncle has posted a drawing several times in this thread, but I don't have a link off-hand. Maybe I can whip one up this weekend and ad it to the site.

[jc03]

Originally Posted by BeanAnimal

If the bulkheads exit the back of the tank (as opposed to the bottom of an external overflow box) the water level will usually end up near the top side of the down turned elbows. The drop from the weir edge to this height will depend on the placement of the bulkheads (which also help dictate the overall depth of the overflow box). You want some headroom there, but the larger the drop, the more chance of waterfall noise you have. Make sense?

On most tanks setup following the published plans and using the 1.5x or 2x diameter from the trim for bulkheads and a weir at the bottom edge of the trim, this leaves a distance between the weir edge and overflow level of an inch or two (depending on flow rate, weir width, box width, etc.)

Follow the general design criteria and you will be fine:

Thanks Bean!

• Center of bulkheads at least 2x the drill diameter from the top edge of the tank.
• Top of weir at bottom edge of trim
• box depth (front to back) enough to get your hands into and fit elbows on bulkheads
• box height (bottom of box) enough to accommodate the down turned elbows with maybe 1/4" to 1/2" clearance, again depending on desired flow.

Uncle has posted a drawing several times in this thread, but I don't have a link off-hand. Maybe I can whip one up this weekend and ad it to the site.

[BlackShark087]

Originally Posted by BlackShark087

Hello,

I run over the thread but I didn't found the answer.

Here is my setup :

http://reefcentral.com/forums/showthread.php?t=2496991

265G Marineland CornerFlow + 125G sump

I have 4X 1" Holes.

I found that other members had issue with the Cornerflow grid making waterflow restriction if the chose the option of one side siphon.

There is also people who had issue of waterfall inside the cornerflow

I also found issue with balancing the siphon from the 2 side can be painfull. (Herbie)

For me the most important is that the system is silent as much possible with the less adjustment and the max flow rate. (yes I want everything)

So here Is my plan :

height of them Rate From ---0+++ / the corner flow grid water level as the 0 / the Factory length of the durso

| Open channel standpipe / Durso 0 | Full Siphon standpipe ---0 | -> Straight to the sump

| Open channel standpipe / Durso -0 | Emergency standpipe 0+ | 2X 45 deg angle run back to the sump

Tank over filling 0+++

Ill Upgrade all the stand pipe to be the same size 1" 1/2 down reducer to 1" bulkhead
4 straight pipe to sump with 3 gate valve

Ill Cover the Cornerflow with a peace of acrylic I dont want anything there, no light, no algua, no nothing.

for Return Ill Run a 1"1/2 pipe up from the side of the tank and build a manifold with 3X 1" return from the top of the tank those 3 gonna split in 2 for a total of 6 water return. Anyway my opinion is that 2 return is not enough. I want to max up the water flow.

My logic behind only 1 Full syphon is to get a pump have a 1" output but with a very High flow rate that im gonna reduce with a gate valve for adjustment to match the exact flow of 1" full siphon with no restriction. so instead of adjusting the overflow Ill adjust the return of water that goes in the tank.

The last thing in consideration is do I go with 2X Open channel standpipe or 2X Emergency standpipe for more safety. Cause im gonna max up the flow for the manifold.

And finally I need to know the flow rate a my full siphon to buy a pump that is going to overrate it. (Ill post back with the specific details about length, height for now is more a concept....

Thanks for you help and bring me all your suggestions.

here some pictures!











here we go :

the holes in the tanks for the bulkhead are around 1" 1/2, a pipe of interior diameter of 1" goes in. for the "durso" there is some reducer and its go up to a pipe of interior diameter of 1 1/2". Now objective is to calculate how much Gph on both direction. the overflow is 5' height and the return is 6' height. Consider that most of all is gonna be run with the 1 1/2" pipe and reduce for the bulkhead and the manifold. How much gph we run ? for the choice of the pump the pipe outside diameter is 1 5/8".

[BlackShark087]

and there is the "0" point

[BlackShark087]

you have any suggestion Beananimal ?

[BlackShark087]

If im right...
Gravity flow :

http://www.calctool.org/CALC/eng/civil/hazen-williams_g

for a 1" pipe of 5' height or full siphon a 4' = 2 500 GPH.

That mean go for safety and 2X emergency

| Full Siphon standpipe ---0 (13") | Emergency standpipe 0+ (27")|

| Open channel standpipe / Durso 0 (25 1/2") | Emergency standpipe 0+ (27") |

and im fully safe and functional !?!

[BlackShark087]

I finaly found this website with all the information I need. http://gmacreef.com/

[adamwheel]

I received some advice on here a couple weeks ago with respect to the c2c overflow on my newly built refugium and have gone back to the drawing board.

I have 3/4" bulkheads but all other PVC is 1" for the plumbing including the standpipes.

My original plans didn't have much of a vertical drop for the siphon. I've reworked them and have a little better scenario and wanted to run it by the experts.

There are no horizontal runs whatsoever. 2.5 ft drop over the course of 3 feet horizontal distance with all 1" PVC. The return to the refugium from the sump is an Eheim 1262 (rated for 900 gph at zero head). I know I'm more likely to get ~600-700 gph but that should be more than enough through a 25 gal refugium.

This sound ok?

As always, thanks,

Adam

[sleepydoc]

Originally Posted by BlackShark087

If im right...
Gravity flow :

http://www.calctool.org/CALC/eng/civil/hazen-williams_g

for a 1" pipe of 5' height or full siphon a 4' = 2 500 GPH.

That mean go for safety and 2X emergency

| Full Siphon standpipe ---0 (13") | Emergency standpipe 0+ (27")|

| Open channel standpipe / Durso 0 (25 1/2") | Emergency standpipe 0+ (27") |

and im fully safe and functional !?!

I can't tell exactly what your proposed setup is from your post, but the theoretical flow from a 1" pipe with a 4 ft drop is about 2500 gph. That ignores friction losses from the pipe. Depending on your plumbing setup they will affect the flow to varying degrees. Unless you're doing something crazy, you should be safe taking a 50% safety margin.

[sleepydoc]

Originally Posted by adamwheel

I received some advice on here a couple weeks ago with respect to the c2c overflow on my newly built refugium and have gone back to the drawing board.

I have 3/4" bulkheads but all other PVC is 1" for the plumbing including the standpipes.

My original plans didn't have much of a vertical drop for the siphon. I've reworked them and have a little better scenario and wanted to run it by the experts.

There are no horizontal runs whatsoever. 2.5 ft drop over the course of 3 feet horizontal distance with all 1" PVC. The return to the refugium from the sump is an Eheim 1262 (rated for 900 gph at zero head). I know I'm more likely to get ~600-700 gph but that should be more than enough through a 25 gal refugium.

This sound ok?

As always, thanks,

Adam

You'll probably be fine; as I said my response to Blackshark, the plumbing & fittings play a significant role in the flow. Theoretical max flow for 1" plumbing with a 2.5' drop is about 2000 gph. The extra pipe, fittings and 3/4" bulkhead will drop that rate a fair amount, but likely not by 2/3.

The actual flow you get from your return pump also depends on the plumbing setup.