Durso stand pipe silencer??

[soupa2]

soupa2 In your second image with the plumbing I see two lines. Would it be possible to put a valve below the tank on the line with the durso?
just remove the elbow and replace it with a strainer and set the flow so that it is submerged and running a full siphon. Then use the other line to take up the small trickle of water turning the overflow into a herbie style.
You may have to shorten the main pipe a little to submerge it completely.
If you have never heard a herbie style drain they are very quiet.

That is a good idea. I rather master the durso setup so in the near future. If all doesn’t go well with noise level than I’m going to try changing it to herbie.

I like big g's idea of turning it into a siphon. Thats why i was asking how many drains u have. Hoping to turn one into an e drain but since you are running the system with out one now no big deal in not having it going forward.....or use the other drain as an e drain. How big are the drain bulkheads ? What gph are you running atm ?

The tank have 4 holes in the back corners with over flow tower. Each side have one 3/4” return and 1.5” drain. I think my pump with the head height, elbows and loc-line are pushing roughly 1600-1700 gph.

 

[monkeybike]

I run the airlines from the top of the durso into the water in the overflow on mine, haven't had an issue in many years of it running. Seems to increase flow somewhat. Most of my noise comes from the siphon break holes spraying water out into the overflow box.

 

[soupa2]

I run the airlines from the top of the durso into the water in the overflow on mine, haven't had an issue in many years of it running. Seems to increase flow somewhat. Most of my noise comes from the siphon break holes spraying water out into the overflow box.

I have that also where I drilled a 1/8” hole where the durso last bend into the straight stand pipe. I than inserted a piece of plastic tube into it to let air and tried adding air pump air into that to create more air but doesn’t silencing it.
Here are the other side of the tank J jaws7777 BIG-G Woefulrelic

 

[jaws7777]

Just a thought since your already mixing air with the tubing and its not improving.


Seems like air isnt being fully purged in that one elbow. This is the longer run right ?

Can you increase gph to see if that helps purge the air ?

Or

I dont know if any of this is possible since i think you have baffles. But can you move one of the sock holders so that but drains are equal lengths ? Could be the long run is trapping the air at that 90.

Or

Last resort i would just rip out the durso and create a full siphon. Might not be ideal but with out the e drains but like we said you dont have them now anyway.

Another thought would be to maybe use the 2 1.5 inch drains as E drains. Then use the 3/4 drains as siphons and run the returns over the back/top into the tank.
Suppose this graph is close to accurate. 2 x3/4 siphons would give you well over your current 1700 gph. You would have to dial the gates in and the 1.5 in e drains x 2 would provide you with a total of 2400 gph of safety. I would absolutely not going anywhere near the max an e drain could handle.

Hope we can all figure something out

 

[Woefulrelic]

You could gate back the flow on the short run drain. I didn't like this idea because with these durso drains you utilize both drains, no emergency back up. If some debris were to clog on either side I worried the tank would overflow.

I think it's some combination of pipe diameter and gravity. Like the drain is taking too much physical water the air can't pull through properly and protein skims the water. I don't really know why it happens but it's been my experience. I was considering adding an air escape on the equivalent of after your 90 and before your flex. I have a run of pvc and I was considering drilling a hole similar to the top of the durso and plugging it with airline that doesn't enter the inside of the pvc to prevent any splash or backflow. Never got around to it...

 

[BIG-G]

In my experience anytime you have to have air mixing with the drain water you will have that rushing water noise and when you rely on an additional hole drilled to act as a siphon break you will hear the sucking noise almost constantly. unless the system is tuned perfectly.

I get that you want to play around with the Durso and a lot of people use them, they can be a reliable method.

But, if you can't get the desired results with the Durso the Herbie drain will perform as close to silently as you can expect. Another thing with the Herbie drain, if you have the main siphon line terminate under water inside the sump it will eliminate the splashing of water exiting the drain, making the sump quieter and less turbulent. Since there isn't any air mixing in the drain.

You can still have the drain empty into filter socks you just have to have the bottom half of the sock submerged so the end of the drain is under water as well inside the sock.