A New Standpipe Thought...

justgettinstarted · #1 10/20/2003, 10:55 AM

A durso on the outside of the tank......

you have your overflow box (now it need only be maybe 1-2" wide... Have nothing but maybe some eggcrate on the bulkhead...

on the outside of the bulkhead:

an elbow pointing UP connected to a T but placed in this orientation |--

and the standard plug drilled... then have another 90 elbow pointing down and then going into the sump....

Depending on the height of the T you can adjust the water level in the tank...

Another thought is using a slipfix between the bulkhead elbow and the T and on the return... and then you could adjust the water level in the tank after its all set up... say for water changes or something...

What do ya think???

justgettinstarted · #2 10/21/2003, 11:42 AM

o really... glad i could help so many people out...

MarkS · #3 10/21/2003, 01:10 PM

Is this what you're talking about?

This is from my plans for a 3000 gallon tank that I am going to build out of wood. I replaced the wood with glass in this rendering for clarity. The plumbing is 4" PVC. I added the 3/4" ball valve so that the air inlet could be adjustable.

There is a member on this board who has already done this and that's where I got the idea from. It is the best way when your overflow is too narrow for an internal Durso and too short for a Stockman.

FishGeeek · #4 10/21/2003, 04:28 PM

check out this thread.

http://archive.reefcentral.com/forum...hreadid=251614

FG

singularity · #5 10/21/2003, 05:34 PM

I made my "modified external Durso" back in June. It is worked really well, and is very quiet.

Here is a thread on ReefCentral about it: http://archive.reefcentral.com/forum...hreadid=215828

I have some pictures up online (of both construction and final design) here: http://www.vampy-alumni.org/octopus/pictures/overflow/

Since that time I have attached eggcrate over the top (but not taken pictures yet)

If you have any questions let me know.

justgettinstarted · #6 10/22/2003, 01:13 AM

well... i guess kinda similar to this... but still quite different...

there would be NO elbow in the tank... because the overflow will only be ~1 to 2" deep... and would be longer than a typical overflow... and the hole for the bulkhead would be significantly below where the water level would be.... so that the distance that the water fell into the overflow would only be perhaps 1/2 to 1"

i will try and draw a picture and load it onto my server sometime tomorrow if i am not to busy

MarkS · #7 10/22/2003, 12:25 PM

Quote:

Originally posted by justgettinstarted
there would be NO elbow in the tank... because the overflow will only be ~1 to 2" deep... and would be longer than a typical overflow... and the hole for the bulkhead would be significantly below where the water level would be.... so that the distance that the water fell into the overflow would only be perhaps 1/2 to 1"

Wont work. The elbow in the tank is what keeps it quiet. Without the elbow, the water would drop just below the top of the bulkhead opening and suck in air. This will be quite loud.

Tarpals · #8 10/22/2003, 02:10 PM

It is all a matter of physics.

Here is a design I came up with for a Durso to replace a HOB overflow for those of us with an un-drilled tank. To prime it you close off a ball valve at the sump level and fill the pipe up with tank water (& a funnel) through the removable air-stack cap. Once water is flowing into the tank you cap the air-stack tight and open the ball valve, and gravity does the rest. Once the vacuum trap is primed the system will continue to operate shutting off the siphon and self-starting through power off and on situations.

Through my prototypes I have found that two 1â€? overflow traps feed a 1.5â€?drain sufficiently and that adjusting the air flow through the raised stack creates quiet operation.

No I have not yet placed this system into practice.
But I would love the input of others before I doâ€¦

Tarpals · #9 10/22/2003, 02:11 PM

And a rear view... too

dsb1829 · #10 10/22/2003, 02:29 PM

Nothing new. Been doing it since 2000.

http://www.rl180reef.com/pages/stand...ug_closeup.htm

Mine was in an external overflow box, but the idea is the same. One thing I recommend is keeping the horizontal distance as short as possible. This will reduce friction and allow a bit more flow.

As others have indicated, the elbow is required in order to create the semi-siphon that makes the Durso possible.

justgettinstarted · #11 10/22/2003, 04:20 PM

YES IT IS DIFFERENT... AND NO IT WILL NOT BE LOUD...

i dont think anyone actually understands what i am saying... so here is a picture...

tomason · #12 10/22/2003, 05:07 PM

justgettingstarted,

I don't see any reason why that wouldn't work....Looks like a really good idea! Very low-profile inside the tank. When you get it going, be sure to post some pics.

-Tom

MarkS · #13 10/22/2003, 05:25 PM

That would work! Great idea! It would be awesome in a nano.

H20ENG · #14 10/22/2003, 05:44 PM

Tarpals,
Welcome to RC!
I cant see your pics, just a red X...
I am interested.

singularity · #15 10/22/2003, 09:22 PM

Your plan should work, but I would have two pieces of advice for anyone attempting it:

1) You are going to need a lot of clearance behind the tank. The tank will have to be moved out a decent distance from the wall. Of course, you make up for it with almost no distance used in the tank.

2) I would keep the plumbing a lot bigger than normal (in diameter). I think you are going to lose a lot of flow with the water making its way through the pipes before it gets to the sump.

Other that those two points, I see no reason why this will not work.

rspar · #16 10/22/2003, 09:38 PM

Thanks for the pics people I just finished my plumbing I tried to go with something like marks but with the elbow up with a screen and no overflow box. Way too noisy even with an air vent. Everything looks the same so I think I can turn the elbow down and just add the overflow box around both of my overflows.

rspar · #17 10/22/2003, 09:54 PM

I'm looking at my setup and my overflow bh's are low does the elbow have to point down. I might end up with something more like "justgettinstarted" because of my bh placement. Or maybe they'll become large returns and I'll redrill for a typical corner overflow with durso. Crud thought I was about done. Also how does the siphon break get plumbed mine obviously doesn't work it's external like your overflow air inlet.

kcolagio · #18 10/22/2003, 10:25 PM

Watch your flow rates guys...

When you have a very narrow area (as pictured above...with the 1/2 inch), you need to watch how much space you have for water going INTO the pipes compared to space for the water to flow through the pipes.

If the water can't enter fast enough, it may be too slow for the return pump, which will result in a flood. That could happen if you only have 1/4 inch of space between the bulkhead "front" and the overflow's wall..

You always want to make sure that your slowest flow rate is from the return pump to the tank. If it (the slowest flow rate) is ANYWHERE else, you are asking for trouble.

MarkS · #19 10/22/2003, 10:44 PM

With standard overflow box. Stockman standpipe not pictured...

MarkS · #20 10/22/2003, 10:48 PM

With new overflow. Drain line gets upgraded from 3/4" to 1 1/2", space in the tank is reduced and the flow can increase. Works for me!

Singularity, your point #1 kind of disappears if you rotate the plumbing like I did in this pic. You'll still need some space, but the required space would be cut in half!

This is a really great mod!

Surf · #21 10/22/2003, 10:51 PM

Seems like an idea, for your 100 gallon tank you'll still need about 15 inches of waterline won't you?

MarkS · #22 10/22/2003, 11:28 PM

Quote:

Originally posted by kcolagio
Watch your flow rates guys...

When you have a very narrow area (as pictured above...with the 1/2 inch), you need to watch how much space you have for water going INTO the pipes compared to space for the water to flow through the pipes.

If the water can't enter fast enough, it may be too slow for the return pump, which will result in a flood. That could happen if you only have 1/4 inch of space between the bulkhead "front" and the overflow's wall..

You always want to make sure that your slowest flow rate is from the return pump to the tank. If it (the slowest flow rate) is ANYWHERE else, you are asking for trouble.

Very good point. I guess a good rule of thumb with this design would be to have at least the distance from the edge of the bulkhead to the inside of the overflow equal to the diameter of the bulkhead. So a 1 1/2" bulkhead would require 1 1/2" between it and the overflow. It could probably be less, but you cannot go wrong with this way of measuring.

MarkS · #23 10/23/2003, 12:38 AM

Here's an update pic showing where the water level will be in the plumbing and overflow...

MarkS · #24 10/23/2003, 12:41 AM

Quote:

Originally posted by kcolagio
Watch your flow rates guys...

When you have a very narrow area (as pictured above...with the 1/2 inch), you need to watch how much space you have for water going INTO the pipes compared to space for the water to flow through the pipes.

I think he meant 1" to 2" in the pic and not 1/2". Still a valid point.

kcolagio · #25 10/23/2003, 06:47 AM

Quote:

Originally posted by MarkS
Here's an update pic showing where the water level will be in the plumbing and overflow...

Very nice picture.

Another thing to keep in mind...you keep marking the water as being in the middle of the pipe coming out of the T....that may not be the case (again, this will depend on the flow rate).

The pictures _look_ like you have the top of the mid-T pipe near the top of the tank...make sure it is a little below that point. Othewise, the pipe won't be completely full when the tank is.

p.s. What software are you using for your modeling? I use 3D Max for mine...