Durso Standpipe

[IcantTHINKofONE]

Ok I set up Durso Standpipes in my overflow to stop the "waterfall" sound. But now, from the fresh air hole at the top of the tee, it sounds like a toilet is flushing 24/7. How do I stop this noise now? And will that produce a new noise? lol

 

[danmhippo]

Whoelse best to answer this question other than Rich?

----------------------------------------------------------------------

Not Durso, but I used to have a u-siphon, that I run the venting hole to a powerhead's venturi. When there are air trapped in the inverted U-siphon, the powerhead venturi adapter will quickly sucked them away.

 

[reefland]

It sounds like a "toilet is flushing" or like a whistle? with the whistle you can usually make the hole slightly larger.

What size tank and what kind of flow (into overflow chambers)

 

[IcantTHINKofONE]

reefland it's a 230 gallon with an 80 gallon sump. The return pumps are two 1800GPH Mag Drives but at 6' so I'm guessing they only pump about 1200 or so GPH at such a height. The overflow box has two 2 inch holes but the PVC down to the sump is 1 1/2"...That's how the guy who made the tank did it. The durso pipes are 2". The flushing seems to have gone away but I still hear the crashing of waves through the airhole as the water flows down the pipe.

 

[SPC]

What size is the "air hole"?
Steve

 

[ReefLion]

Yes it sounds like the hole might be too big. At the same time, with that flow, you might need a hole that size to prevent siphoning. If so, you can connect hose to the hole and run the hose to a place where you can muffle the noise (under the tank, behind a wall, etc).

Note that if you do this, the hose typically needs to be significantly wider than the airhole, to allow good flow of air to the hole. If you drill the hole just wide enough to prevent siphon, but then attach a long hose to it that's only as wide as the hole, you will then diminish the airflow enough to create the siphon.

 

[M.E.Milz]

Sorry to hop in on this, but I have always wondered why using an airhole that is too large causes the water level to rise? I have actually seen why his happens, but I am still unclear as to the reasons. Is it because the goal is to have an airhole that is just big enough to cause a partial syphon? Does too much air in the top of the standpipe create turbulence that reduces the flowrate through the drain? A better understanding of this might help me to "tweak" the system.

Thanks, Mike

 

[IcantTHINKofONE]

My airhole is the top of the 2" tee at the top. Therefore, it is 2". Should I put a cap on it and drill it smaller?

 

[IcantTHINKofONE]

Here's a pic....Sorry it's sideways but I don't have an art program to render it.

 

[SPC]

Posted by I

Therefore, it is 2". Should I put a cap on it and drill it smaller?

-This is what I thought you had. Most people place an end cap on the top of this and then drill a hole in the end cap. What I did was to place an inside reducing bushing (2" to 3/4") inside the 2" pipe, then a short pc of 3/4" pipe with a 3/4" ball valve attached to this. What this does is allow you to adjust the amount of air and not have to guess what size hole to drill.
Steve

 

[ReefLion]

Right. Without the end cap, you basically have an open standpipe. You need to cap it and drill a hole, or do what Steve said. The small hole limits the soundwaves that can escape, reducing the noice considerably.

Mike, a partial siphon will reduce the water level in the overflow box. I don't know what Rich does with his, but I personally don't like using a partial siphon, because if it becomes too strong due to fluctuations in water pull or water entering the overflow, then you can pull the water down below the input level and get the toilet sound. I prefer a hole large enough to eliminate siphon entirely, which makes the standpipe essentially an overflow system. The water level will rise to whatever point it would be if you took the cap off. If the hole I need is too big to effectively contain noise, I attach some hose and lead the sound somewhere where I can muffle it.


I have a tank set up like this. I owe someone pics of my sump system, so I will try this weekend to figure out my (gift) camera and how to post pics, then I'll post the whole thing.

 

[Bob Gardner]

It was suggested to me that if you drill a hole in the end cap to take an airline fitting and then add a short length of airline with an airline valve stuck in it. Just adjust the valve to achieve the correct air flow.
Bob

 

[IcantTHINKofONE]

I don't have room for a valve because the pipe is pretty high and the top of the tank has a glass cover covering half the overflow which is siliconed on (don't know why, thats how it was made). What size hole should I drill in the endcap? It's 2" pipe.

 

[SPC]

Start with a 1/4" hole. Make sure you don't glue the end cap on :wink: .
Steve

 

[M.E.Milz]

Right. Without the end cap, you basically have an open standpipe. You need to cap it and drill a hole, or do what Steve said. The small hole limits the soundwaves that can escape, reducing the noice considerably.

Mike, a partial siphon will reduce the water level in the overflow box. I don't know what Rich does with his, but I personally don't like using a partial siphon, because if it becomes too strong due to fluctuations in water pull or water entering the overflow, then you can pull the water down below the input level and get the toilet sound. I prefer a hole large enough to eliminate siphon entirely, which makes the standpipe essentially an overflow system. The water level will rise to whatever point it would be if you took the cap off. If the hole I need is too big to effectively contain noise, I attach some hose and lead the sound somewhere where I can muffle it.


I have a tank set up like this. I owe someone pics of my sump system, so I will try this weekend to figure out my (gift) camera and how to post pics, then I'll post the whole thing.

I agree. That is the way I have it set-up - plenty of airholes to prevent any syphoning. But I did play around with cover some of the holes with tape, and it did lower the water level a bit. But this still leaves me to wonder why this would be of any advantage?

 

[IcantTHINKofONE]

I made a 3/4" hole in the top of the cap and it's flowing just as well as it was with a 2" hole and 10x quieter!! Thanx!