Silent and Failsafe Overflow System

[Bent]

So why exactly would my open stand pipe be siphoning and my siphon stand pipe just trickling? It really doesn't make much sense to me.

The open stand pipe shouldn't be siphoning since it has the tube sticking out the top of it, right?

All 3 exits in the sump are under water. Would that be a reason?

 

[SaltwaterNoob17]

:strooper:

you should talk with metamorphis - he/she is putting together a 500 gallon tank, too.

To (try and) answer your questions:
If you do a bean overflow, going down, under the slab then back up to the sump will be problematic in many ways. Beyond the logistics and expense of setting it up, cleaning and troubleshooting will be difficult and it is more difficult to get a siphon established with a horizontal run; I would have serious concerns about the function of the siphon drain with this configuration.

The resistance of the pipe is a potential concern, but probably not one that can't be overcome. There are sites that go over the equations; It's late and I'm tired, so I can't think of them off hand, but it's definitely doable.

Thanks, sleepydoc. Yeah, I had a feeling that going under the slab wouldn't be smart for this scenario. I know that I want my sump for the aquarium located in that separate 'fish room'. What's the ideal plumbing design in that case?

 

[sleepydoc]

Thanks, sleepydoc. Yeah, I had a feeling that going under the slab wouldn't be smart for this scenario. I know that I want my sump for the aquarium located in that separate 'fish room'. What's the ideal plumbing design in that case?

Well, it depends on the setup.

Ideal is to have the fish room immediately behind or underneath the tank, but it sounds like your fish room will be some distance away. It may be possible to do a bean setup in that scenario, but I honestly don't know.

If you were to try a bean setup with this you'd likely have to have the pipes on a continuous slope, but that would be a drop of about 5' over a run of 10' - pretty shallow. Try posting your question as a new thread in the DIY section. I think you'll get more people viewing it with more ideas there.

 

[sleepydoc]

So why exactly would my open stand pipe be siphoning and my siphon stand pipe just trickling? It really doesn't make much sense to me.

The open stand pipe shouldn't be siphoning since it has the tube sticking out the top of it, right?

All 3 exits in the sump are under water. Would that be a reason?

I just looked at the pics you posted a while back and I'm confused - you appear to have 2 drains inside the overflow, one turned up and the other turned down, and a 3rd outside the overflow. in addition you have the overflows connected to vinyl tubing that goes through the wall. Where is your sump?

 

[Bent]

I just looked at the pics you posted a while back and I'm confused - you appear to have 2 drains inside the overflow, one turned up and the other turned down, and a 3rd outside the overflow. in addition you have the overflows connected to vinyl tubing that goes through the wall. Where is your sump?

Well the sump is in my basement, so the drain goes through the wall to the basement. Like so:

(Ignore the fact that the drains aren't plumbed in this pic. They go to the 3 elbows on the right.)

The water level sits right above the drains.


Also in the pic I showed you, both of the elbows inside the overflow box are pointed down, I just forgot to turn one in the pic. The elbow outside of the overflow is the emergency pipe. I didn't have enough room in the box to plumb it inside. Didn't figure it would matter much.

 

[Reefer PT]

Internal to External overflow questions

Internal to External overflow questions

Just looking for confirmation. standard 120gal tank. Internal weir is C2C at 2" deep by 5" high. External Box I would like to do a 30"X 8"high by 3.5" deep box with 3 1" bulkheads in bottom of box and 1.25 pvc after bulkhead, BA drain. All glass using Momentive RTV silicone. For the holes between the boxes I found this drawing.

Now I was hoping to use the same hole saw as for the 1" bulkheads and only do 3-4 holes in the back of the tank.
1.Do you think using a 45mm hole and reducing the hole count would be detrimental or I should stick to the drawing and do a C2C external box too?
2. Do these holes b/t the internal and external need to have bulkheads on them to strengthen the glass?
3. Do the dimensions of the boxes seem right?
Thanks for your help.
Dave

 

[Skydivingcat]

So why exactly would my open stand pipe be siphoning and my siphon stand pipe just trickling? It really doesn't make much sense to me.

The open stand pipe shouldn't be siphoning since it has the tube sticking out the top of it, right?

All 3 exits in the sump are under water. Would that be a reason?

Your open channel is running in full siphon? If so it can not be open.

 

[Bent]

Your open channel is running in full siphon? If so it can not be open.

It's not full siphon, but it's fast. Maybe the line I have out of it is not big enough?

 

[Swope2bc]

It's not full siphon, but it's fast. Maybe the line I have out of it is not big enough?

Is your full siphon line wide open (the adjustment valve)? If so it would seem your flow is just a bit high for your plumbing. Perhaps neck back your return a bit.

 

[Bent]

Is your full siphon line wide open (the adjustment valve)? If so it would seem your flow is just a bit high for your plumbing. Perhaps neck back your return a bit.

That's a good idea, I've never tried turning down the return line. I'll give that a shot tonight.

 

[Skydivingcat]

That's a good idea, I've never tried turning down the return line. I'll give that a shot tonight.

Why would you want to reduce flow?

 

[Bent]

Why would you want to reduce flow?

Beats me but I'm willing to try anything at this point.

 

[Swope2bc]

Why would you want to reduce flow?

If his open line is flowing too much water then it is apparent that his full siphon is not keeping up with his return.

 

[Reefer PT]

anyone?

 

[Skydivingcat]

If his open line is flowing too much water then it is apparent that his full siphon is not keeping up with his return.

That seems like the backwards way to do it. Seems to me you should determine the flow required for your tank then size return and drain to meet those requirements.

I think in the three hundred or so pages in this thread this is the first time that the siphon drain could not keep up with the return flow.

 

[sleepydoc]

That's a good idea, I've never tried turning down the return line. I'll give that a shot tonight.

Replied to your other thread - What is your flow? My guess is your plumbing is the issue. How big is the vinyl tubing? A standard 1" pvc pipe can handle well in excess of 1500 gph when dropping 8', but the vinyl tubing is probalby throttling the system. At very least it's probalby causing problems with the open channel. For the system to start up properly, the water level needs to rise to the emeregency drain and stay up long enough for the siphon to purge the bubbles, then it will gradually drop down to steady state. this also depends on the open channel never coverting to a siphon.

Also, where do you have the valve for your siphon? If you have it up top, the negative pressure caused by the siphon can cause the viny tubing to collapse

 

[sleepydoc]

Just looking for confirmation. standard 120gal tank. Internal weir is C2C at 2" deep by 5" high. External Box I would like to do a 30"X 8"high by 3.5" deep box with 3 1" bulkheads in bottom of box and 1.25 pvc after bulkhead, BA drain. All glass using Momentive RTV silicone. For the holes between the boxes I found this drawing.

Now I was hoping to use the same hole saw as for the 1" bulkheads and only do 3-4 holes in the back of the tank.
1.Do you think using a 45mm hole and reducing the hole count would be detrimental or I should stick to the drawing and do a C2C external box too?
2. Do these holes b/t the internal and external need to have bulkheads on them to strengthen the glass?
3. Do the dimensions of the boxes seem right?
Thanks for your help.
Dave

Don't have time to write more, but in general:
It depends on your flow.
You don't have to have the external box be coast to coast, but you do need enough holes/area to allow the water to flow relatively unimpeded
The holes should be about at the same height as the water level which is set by your plumbing
Bulkheads do nothing to strengthen the glass
If yoour external box will be glass, make sure it is large enough to drill the holes without compromising the integrity.

 

[Bent]

Replied to your other thread - What is your flow? My guess is your plumbing is the issue. How big is the vinyl tubing? A standard 1" pvc pipe can handle well in excess of 1500 gph when dropping 8', but the vinyl tubing is probalby throttling the system. At very least it's probalby causing problems with the open channel. For the system to start up properly, the water level needs to rise to the emeregency drain and stay up long enough for the siphon to purge the bubbles, then it will gradually drop down to steady state. this also depends on the open channel never coverting to a siphon.

Also, where do you have the valve for your siphon? If you have it up top, the negative pressure caused by the siphon can cause the viny tubing to collapse

The vinyl tubing is also 1" ID. (Of course it is restricted a tad by the smaller nipples that you clamp the tubing too.) The open channel seems to be hogging all the flow. On start up, even with the siphon channel valve completely closed, the water level never makes it down the emergency pipe before the open channel just starts draining the box like mad.

Sigh. I'm going to have to replumb this aren't I?

 

[Reefer PT]

Don't have time to write more, but in general:
It depends on your flow. About 1000gph after head loss
You don't have to have the external box be coast to coast, but you do need enough holes/area to allow the water to flow relatively unimpededfor 45mm holes is 3 enough then? Or is 4 better?
The holes should be about at the same height as the water level which is set by your plumbing
Bulkheads do nothing to strengthen the glass
If yoour external box will be glass, make sure it is large enough to drill the holes without compromising the integrity. so is 3.5" too narrow then? From other posts on this thread that seemed to be a common dimension. Just want to know what is best..

 

[uncleof6]

Just looking for confirmation. standard 120gal tank. Internal weir is C2C at 2" deep by 5" high. External Box I would like to do a 30"X 8"high by 3.5" deep box with 3 1" bulkheads in bottom of box and 1.25 pvc after bulkhead, BA drain. All glass using Momentive RTV silicone. For the holes between the boxes I found this drawing.

Now I was hoping to use the same hole saw as for the 1" bulkheads and only do 3-4 holes in the back of the tank.
1.Do you think using a 45mm hole and reducing the hole count would be detrimental or I should stick to the drawing and do a C2C external box too?
2. Do these holes b/t the internal and external need to have bulkheads on them to strengthen the glass?
3. Do the dimensions of the boxes seem right?
Thanks for your help.
Dave

1) It depends. You want the internal and external to be one body of water. Hence no water level change, with water level at the center of the hole. The more "freely" the internal and external box communicate, the better off you will be. The implication is: you are not using the full diameter of the hole. Therefore what might appear to be overkill, may well be under kill.

2) You don't want any bulkheads in the holes. It will restrict the communication between the internal and external boxes. This is just one of the potential issues with the "ghost overflow" line of thought, that requires such bulkheads to hold everything together. One body of water, with waterline at the hole center line, is what you want.

3) The dimensions of the boxes, depends on the size of the pipe/fittings. It also depends on having the proper height differences between the inlets to the standpipes. Essentially, the tops of the down-turned elbows will be just a bit above the waterline. (slight variations.) So the final practical dimensions are up to you to determine, by measuring the plumbing etc, so everything ends up where it needs to be.