Silent and Failsafe Overflow System

[mmn]

Two things come to mind.
1. Restriction in return flow
2. Increase in siphon flow.

 

[cryptic_grower]

Two things come to mind.
1. Restriction in return flow
2. Increase in siphon flow.

I haven't adjusted the valve on the siphon line at all ,since initial set, I don't think that is it. My return is unrestricted, as far as valves go anyway. So the "slime coat" in my return can account for that much of a drop in flow?

 

[mmn]

I haven't adjusted the valve on the siphon line at all ,since initial set, I don't think that is it. My return is unrestricted, as far as valves go anyway. So the "slime coat" in my return can account for that much of a drop in flow?

Maybe the pump is slowing or something got caught in there? Or somehow the flow over your weir has decreased?

 

[sleepydoc]

Two things come to mind.
1. Restriction in return flow
2. Increase in siphon flow.

+1
Check your return pump to make sure nothing is impeding return flow. If you don't find anything I would just adjust the gate valve and keep an eye on it.

 

[sleepydoc]

It's real tough to tell which one is making it. I stood on a ladder over it for ten minutes and heard it twice. I opened the siphon a little more and it seems like it slowed a bit. The level in the box is now at about the midway point of the bulkheads or slightly lower. I also can't tell if there are any bubbles because the sump is a 100 gallon stock tank you can't see through.

The sound isn't really a burp. It's more of a fairly slow gurgle. I also plugged the open channel air line and nothing happened. Is this normal? Thanks.

If the flow is low enough in the o pen channel that can happen. Is either of the intakes in the overflow creating a vortex and entraining air?

 

[Pprice01]

I'm running ~1200 gph; 1.5" pipes, 1" bulkheads and 1.25" elbows in a coast to coast overflow. Approx ¾" between the bottom of the overflow and the bottom of the elbow. Water depth is 2 ¾", so about 2" from the surface to the bottom of the elbow. If the water depth drops much below 2 ¾" it starts entraining air from the surface. Not a lot; the bubbles sound like some sand or small pebbles running down the pipe, so it's not terribly noticeable, but it is there. Of course, once my skimmer is turned on, it's inaudible.



What size elbow are you using? if you can use a 1.5" elbow, the edge flow velocity will be lower and it will probably be less likely to entrain air. I don't have a good feel for when the gap between the elbow and the bottom of the overflow becomes an issue; you could try cutting it down to ½" and see how it goes. As long as you don't cement you elbows in place it's easy to take it out and trim another ¼" off.

Thanks sleepydoc. I am now putting the theory into practice,by finally setting up the plumbing.

Question, I've heard that fish have a tendency to get into the overflow box when no teeth are present on the weir. Opinions on this?

If this is true, would it be better to leave only an 1/8" gap between the floor of the box and the bottom of the street 90 - IF I cut, say, 1/4" teeth all the way around the bottom of the fitting? I could easily do this on the table saw.

I'm wondering if this would help me achieve better flow while also keeping critters out of my siphon or if this is a bad idea.

Thoughts? Thanks everyone.

Here's my overflow box (ignore the RO tubing, I'm using it to fill the tank):



And the start of my plumbing on the outside:

 

[jc03]

+1
Check your return pump to make sure nothing is impeding return flow. If you don't find anything I would just adjust the gate valve and keep an eye on it.

I stood on a ladder and watched it for a decent time. It looks like there is a vortex being created near the full siphon right about when you hear the slurp. How do I eliminate that? Thanks again.

 

[woodnaquanut]

I stood on a ladder and watched it for a decent time. It looks like there is a vortex being created near the full siphon right about when you hear the slurp. How do I eliminate that? Thanks again.

How deep is the full siphon?

You might be able to close the siphon's valve just a little to get the water level up to prevent the vortex.

 

[jc03]

How deep is the full siphon?

You might be able to close the siphon's valve just a little to get the water level up to prevent the vortex.

They're 2" bulkheads with street 90s and the water height is about dead middle of the bulkhead. It falls about 2" from the weir. I'd have to get an exact measurement tonight.

I did close the valve a bit on the full siphon and I feel like it through a bunch of water into the open channel though. You figure I try that again?

 

[woodnaquanut]

They're 2" bulkheads with street 90s and the water height is about dead middle of the bulkhead. It falls about 2" from the weir. I'd have to get an exact measurement tonight.

I did close the valve a bit on the full siphon and I feel like it through a bunch of water into the open channel though. You figure I try that again?

If the intake of the siphon is too close to the surface it is going to vortex and suck air. Any way you can lengthen the down turned portion of the siphon (long shot since I read you glued it in)? Of course if the siphon doesn't have much room between it and the bottom of the OF, you might be getting a slurp from there too.

If you can get the water level up just a slight bit that might be enough to prevent the vortex. Make tiny adjustment to the siphon flow. As long as the open drain flow is not making noise, there should be no problem running more flow in there.

You probably don't want to do it but reducing the return flow should help too.

Any chance you could post a pic? Time to get back on the ladder!!

 

[sleepydoc]

They're 2" bulkheads with street 90s and the water height is about dead middle of the bulkhead. It falls about 2" from the weir. I'd have to get an exact measurement tonight.

I did close the valve a bit on the full siphon and I feel like it through a bunch of water into the open channel though. You figure I try that again?

With mine I found that closing the gate valve a bit would shunt more to the open channel and reduce the flow in the siphon, minimizing air entrainment from vortices. You can try doing that to see if you get a happy medium where there isn't too much flow in the open channel to make noise.

After that the ways I can think of to fix/reduce it are reducing the overall flow, increasing the size of the intake elbow, and increasing the depth of bottom of the elbow.

I you could somehow affix some sort of flange around the elbow to widen the area from which it draws water down from the surface, that may help as well, but that's not terribly practical.

 

[sleepydoc]

Thanks sleepydoc. I am now putting the theory into practice,by finally setting up the plumbing.

Question, I've heard that fish have a tendency to get into the overflow box when no teeth are present on the weir. Opinions on this?

If this is true, would it be better to leave only an 1/8" gap between the floor of the box and the bottom of the street 90 - IF I cut, say, 1/4" teeth all the way around the bottom of the fitting? I could easily do this on the table saw.

I'm wondering if this would help me achieve better flow while also keeping critters out of my siphon or if this is a bad idea.

Thoughts? Thanks everyone.

You don't want to place the elbow too close the the floor of the overflow as it will restrict flow. I generally haven't had too much problem with fish getting into my overflow. Two approaches I have seen are to put some egg crate in the overflow so if the fish do get in there they can't get to the siphon intake, or to make a cover with a lip on it something like this

 

[ezuc]

Anyone with advice on doing beananimal with 54g quarter cylinder tank.

Tank has corner overflow that is predrilled (bottom) with a 1" and a 3/4". I was planning to use the 3/4" as the siphon and 1" as the open channel and drill a 1" for the emergency.

Does this make sense? Does the height/placement of the emergency matter provided that it's above the open channel?

Appreciate the help!

 

[redcoatd]

Converting Herbie style to BeanAnimal

Converting Herbie style to BeanAnimal

I'm looking at purchasing a new tank - 156g - that has some kind of Herbie system on it. It has a 1 1/2" bulkhead at each side of the back, 3" down from the top, and a single 1" return in the middle of the back.

It doesn't have an overflow box of any kind, so I'll plan on adding a glass coast to coast all the way along the back.

Hoping the pic attachment works.

Any suggestions on where to drill the 3rd 1 1/2" bulkhead?

Is there any problem with the return where it is?

cheers!

 

[sleepydoc]

Anyone with advice on doing beananimal with 54g quarter cylinder tank.

Tank has corner overflow that is predrilled (bottom) with a 1" and a 3/4". I was planning to use the 3/4" as the siphon and 1" as the open channel and drill a 1" for the emergency.

Does this make sense? Does the height/placement of the emergency matter provided that it's above the open channel?

Appreciate the help!

This configuration is more suited to a Herbie setup than a bean, but you could make it a bean if you drill for an emergency as you describe. Do you have room for all 3 pipes in your overflow? many corner overflows get pretty cramped.

Verify that the glass (both bottom and sides) is not tempered before you drill. Where were you planning on drilling? You need to allow at least one diameter distance between glass edges. The typical 1" bulkhead needs a 45mm diameter hole, so the edge of any hole you drill needs to be at least 45 mm from either the nearest hole, or the edge of the glass.

 

[sleepydoc]

I'm looking at purchasing a new tank - 156g - that has some kind of Herbie system on it. It has a 1 1/2" bulkhead at each side of the back, 3" down from the top, and a single 1" return in the middle of the back.

It doesn't have an overflow box of any kind, so I'll plan on adding a glass coast to coast all the way along the back.

Hoping the pic attachment works.

Any suggestions on where to drill the 3rd 1 1/2" bulkhead?

Is there any problem with the return where it is?

cheers!

Why do you need a 3rd bulkhead, and why 1.5"? Easiest way to do the return is up over the top. That way you can make your overflow with two straight pieces of glass.

 

[mmn]

^! It's what I did. People think that return over the top is unsightly, but it actually sort of "disappears" - especially if you paint it.

 

[redcoatd]

Well, I'm pretty sure the current 1" return is not drilled at the same horizontal level as the existing 2 x 1 1/2" bulkheads. Unless I'm missing something, I need another at the same level?

I was thinking 1 1/2" so that everything would be uniform, and match the existing two?

For the return, I was thinking I could put one of those black knobbly pipes (is there a proper name for those?!) on it and direct it over the top of the overflow? Having 2 pieces of glass for the overflow is very appealing...

cheers!

David

Why do you need a 3rd bulkhead, and why 1.5"? Easiest way to do the return is up over the top. That way you can make your overflow with two straight pieces of glass.

 

[redcoatd]

Here's a side view...

 

[ezuc]

This configuration is more suited to a Herbie setup than a bean, but you could make it a bean if you drill for an emergency as you describe. Do you have room for all 3 pipes in your overflow? many corner overflows get pretty cramped.

Verify that the glass (both bottom and sides) is not tempered before you drill. Where were you planning on drilling? You need to allow at least one diameter distance between glass edges. The typical 1" bulkhead needs a 45mm diameter hole, so the edge of any hole you drill needs to be at least 45 mm from either the nearest hole, or the edge of the glass.

I will be tight. Really depends on whether or not the pipes need to be turned down or can just be open on the top?

The bottom is tempered, but already drilled. Thanks for the advice on spacing from the edge of the tank. I didn't know that. I'll need to double check to see if there is enough space.

Wondering if it going to be easier to go with Herbie plus a float switch to the return pump as the "emergency"?