I implemented the Durso modification to my standpipe, and the noise is less, but the stand pipes still make a loud gurgling noise (the noise comes from the pipes themselves). The stand pipes are 1 1/4 inch connected to one-inch overflow drains. Between the two standpipes, I probably have 1200 gph flow.

I have tried larger and smaller air holes to no avail. The only thing I can come up with is that the top of my stand pipe is higher than in the pictures I have seen.

Has anyone achieved silence (or close to it) with a Durso modification? If so, what did you do?

I used it on a hang on overflow and have had complete sucess. I do not know the similarities between mine and yours, but did you drill holes in the pipe or cut a square knotch out? Mine has the square knotch in lieu of drilled drain holes.

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Paul C
The important thing is not to stop questioning.
Einstein

vas,
Is this an intermitent "rush" which sucks all the water from behind the spillway? (usually every 45-60 seconds?)
Or just a continuous gurgle?
later,



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-schrocat

"Whacha got in the box?"

on the top of your duraso do you have a small hole in the cap?? An air vent this may help with the gurgle.Hows the tank??

The noise is a constant gurgle. The water level in the overflow stays constant unless I make the hole in the top too small - then it siphons down to the intake.

The stand pipe is about 22 inches high, and it is 1 1/4 inch all the way to the bottom if that makes any difference.

I have tried a variety of solutions to the hole in the tope - everything from 1-4 1/16th inch holes to a 1/4 inch hole. Not much different except for the volume of the hissing I get from the hole.

I tried to set up the air hose outlet in the air hole, but even when it was fully open, the stand pipes siphoned the water down to the intake.

Other than the noise, the tank is doing great. I have added a Randall's shrimp goby with his shrimp friend and a cleaner shrimp. The next day, one of the shrimp molted and I had to convince everyone that it was not a dead shrimp.

vas,
Can you describe your return plumbing from the bulkhead to the sump?
PVC or vac...angles etc.
later,


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-schrocat

"Whacha got in the box?"

I have a Tenecor 180 with their large overflow. The overflow has 2 one-inch bulkheads at the bottom. I have a reducer attached to the 1-1/4 inch standpipes, which lead up to the durso modified intakes.

Below the tank, space is tight. I have one-inch pvc that goes straight down about 3 inches, then a hard 45-degree angle towards the center of the tank, then 6 inches of hard pvc with ball valves, then another 45-degree turn to head straight down into the sump. I had hoped that the 45-degree turns would minimize water disruption.

The noise seems to come from the standpipe in the overflow. It is not loud under the aquarium.

I have been considering the variation of the Durso modification described at http://home.att.net/~rstockman/overflow.htm

Your pumping 1400 GPH down a 1-1/4 inch durso, then through a 1" pipe. The pipeing under the aquarium is probbly quiet because it is filled. A 1" pipe is supposed to hangle 700 gph of flow. To mw with the flow rates, your alomost maxing out the plumbing, so everything is rushing down the pipes and sucking in air.

Is the noise comming from the hole by chance? I've had to use a small piece of flexible air line tubing and stuff it in the hole just a little bit and it silences it.

Can you throttle back your pump a bit and see if that helps any also?

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- Eric

[This message has been edited by IFLY2HIGH (edited 12-28-2000).]

When I made the Durso pipe for Sole's 150 gal reef, I had to made a mod as well. I just drilled like 10 holes on the pipe itself. That allowed more water inside the pipe, but because the holes are under the water line, they don't suck any air.
You can't hear the pipe even if you put your ear next to it.
(I tried that of course [img]/ubb/biggrin.gif[/img] )



Joaco

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My webpage Updated 14th September 2000

Vas,
I tried the "Durso pipe" for my 75 Tenecor. It just would not work for me. I had an unpleasant waterfall noise because the water dropped down 3", I could not make the pipe taller because of space restrictions with the added cap. I also had the gurgle you describe. I finally scrubbed the Durso and followed the advice of a friend. What I did is remove the inverted T, raised the pipe and placed a bioball on the top of the pipe and voila, no noise. The bioball is the type which looks like a bunch of pipes. I have to have mine at an angle for the lowest noise level. It is my understanding that the Durso" model leads to some pollution in the overflow because the intake is under water and therefore does not skim the surface very well.

I still have a gurgle problem if the water in the sump drops below the end of the drain tube. I just have to cut the tubing a little. Haven't gotten to that yet, but that's minor compared to the world war II noise I had before!

Hope this helps

Claude

Thanks for the sugestions. I'l play with it this weekend and let you know what happens.

Extend your overflow pipe below the water level in your sump. With no place for the air to go but up this will minimize your noise. I have done this and it works quite well.


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Shade & Sweet Water
Brian


Brian@reefland.com