Durso help

[tosiek]

Ok currently on my 44g i have a 1 inch drain and 3/4 intake. Running a durso and i can't get it working properly without letting me sleep the night in peace. I have a 1/16 hole currently and the pump is rated at 660gph but is set at half because its the quietest right now with the durso. The pump is rated at 265gph or so at 3ft head (GenX 2400 ). Piping from my sump to the tank is around 3-4 feet. Durso is 1 1/4" reducing into 1 inch. I've gone through hole sizes from 1/18 - 1/4 and i think i even tried half inch.

with the 1/16 i can keep the pump running super quiet for about 4 mins till the siphon kicks in with the pump at 60-70% then i'm stuck with a 2 inch ocillation of the wate level in the sump. I increase the hole a bit and i get a constant mini flush.

Anyone able to stop by and help me figure this thing out? or able to give me pointers? nothing i am doing is working. I've been through all the faq listings and help on these things.

Thinking of going stockman and saving myself all the troubles.

 

[nemo]

I bought uncut blue bonded filter pad, fold it over once, punch a hole though the top portion of the filter pad, pleace the filter in the overflow and tie the other end of the string to the dursk to anchor the pad.
The pad will then capture the water which muffles the splashing effect of the falling water. Make sure you hang the filter bag high enough so it does not block the drainage.

 

[bad coffee]

Do yo have a reducing bushing in the durso? I've read you definatly need it to work.

can you take a picture of your setup?

Also, is your overflow to the sump submerged or above the water line?

B

 

[tosiek]

Its reduced from 1 1/4 inch to 1 inches before it hits the bulkhead in the overflow. And the drain is submerged with a 45 degree elbow at the end.

 

[bad coffee]

have you tried putting a ball valve on the overflow to give it just a bit of back pressure?

B

 

[tosiek]

There is a ball valve on the line going down. I don;t want to reduce the drain in a chance of it overflowing my tank =0)

 

[meschaefer]

Ok currently on my 44g i have a 1 inch drain and 3/4 intake. Running a durso and i can't get it working properly without letting me sleep the night in peace. I have a 1/16 hole currently and the pump is rated at 660gph but is set at half because its the quietest right now with the durso. The pump is rated at 265gph or so at 3ft head (GenX 2400 ). Piping from my sump to the tank is around 3-4 feet. Durso is 1 1/4" reducing into 1 inch. I've gone through hole sizes from 1/18 - 1/4 and i think i even tried half inch.

with the 1/16 i can keep the pump running super quiet for about 4 mins till the siphon kicks in with the pump at 60-70% then i'm stuck with a 2 inch ocillation of the wate level in the sump. I increase the hole a bit and i get a constant mini flush.

Anyone able to stop by and help me figure this thing out? or able to give me pointers? nothing i am doing is working. I've been through all the faq listings and help on these things.

Thinking of going stockman and saving myself all the troubles.

My durso is dead quite. What typ of noise are you getting. Is it a gurggling sound, or a flushing sound.

Gurgling is cause by to big of a hole. There are a lot of hole sizes between 1/4 and 1/2.

If you are getting a mini flush, you need to increase the size of the hole. The mini flush happens because a siphon is being created. Not enough air is getting into the system so the water flow is constricted, untill the level rises a little in the overflow, then it siphons out. Bigger hole fixes this. I have about 600 gallons or so running though my durso, and I think I used slighlty larger than 1/4 inch hole. You need to start small and slowly increase the size of the hole untill it is quite.

The other thing that you need to look as is the drain into the sump. you will get a flush and a lot of noise if the outlet on the drain in the sump is constricted in any way, i.e the drain pipe touches the bottom of the sump or is dumping the water into a corner of the sump. This happems because the water can't exit the pipe fast enough, causing back pressure. When the back pressure happens, the durso slows down untill the water level in the overflow starts to rise. Once again, it will rise untill the water pressure from the overflow is enough to over come the back pressure at the outlet in the sump, and then it will flush out. Very noisey.

 

[Psycho graphic]

There is a ball valve on the line going down. I don;t want to reduce the drain in a chance of it overflowing my tank =0)

This is my thoughts on this and somone correct me if I'm wrong.

Many years ago I built and setup a W/D with an OFB for a friends FW tank. I used clear flexible tubing to connect the OFB to the W/D. I had installed a ball valve on the W/D intake and one on the output of the return pump. The initial settings had both valves wide open.

Upon starting it up I had to throttle back the return to balance things out and let it run about an hour to make sure it stayed in balance. The OFB was making the normal amount of noise everyone complains about. The noise was obviously air getting sucked into the drain, it was visible through the flexible tubing.

I then figured the flow was to fast through the OFB and would not allow the bubbles to fight gravity and then throttled back the OFB until the trapped bubbles could defeat the flow and rise up the tubing. I then played with this valve until I got it to where it was running as far open as possible without allowing air to enter.

After doing this, the return pump needed to be opened as the balnce was off again, this time in favor of the OFB. I opened up the return and got it balanced again.

To me this means you are actually losing flow by allowing air to replace some of the volume available, that should have water in it. In other words adding a valve to restrict air from entering the tubing, you actually are increasing your flow.

Am I correct in thinking this is true?

 

[meschaefer]

This is my thoughts on this and somone correct me if I'm wrong.

Many years ago I built and setup a W/D with an OFB for a friends FW tank. I used clear flexible tubing to connect the OFB to the W/D. I had installed a ball valve on the W/D intake and one on the output of the return pump. The initial settings had both valves wide open.

Upon starting it up I had to throttle back the return to balance things out and let it run about an hour to make sure it stayed in balance. The OFB was making the normal amount of noise everyone complains about. The noise was obviously air getting sucked into the drain, it was visible through the flexible tubing.

I then figured the flow was to fast through the OFB and would not allow the bubbles to fight gravity and then throttled back the OFB until the trapped bubbles could defeat the flow and rise up the tubing. I then played with this valve until I got it to where it was running as far open as possible without allowing air to enter.

After doing this, the return pump needed to be opened as the balnce was off again, this time in favor of the OFB. I opened up the return and got it balanced again.

To me this means you are actually losing flow by allowing air to replace some of the volume available, that should have water in it. In other words adding a valve to restrict air from entering the tubing, you actually are increasing your flow.

Am I correct in thinking this is true?

By adding air into the overflow I guess you are technically reducing flow, but the trick is that the overflow should match what is being returned ot the tank. The gurggling sould that occurs is due to the overflow sucking in air because you are never running the overflow at its max capacity, this wold be a receipe for disaster. The trick is to get just enough air into the overflow so that it runs smooth.

IMO you do not want to, nor do you need to restrict the overflow with a ball valve. If you are doing this, you have a problem someplace else should be addressed. By restricting the overflow with valve, you are reducing the capacity of the overflow to match the amount of water being returned to the tank, i.e. it is running at max capacity.

What happens when the durso get clogged by a peice of debris, snail, small fish, a chunk of algae....etc etc. You tank will overflow.

 

[Psycho graphic]

A pipe filled with water and nothing else, makes no noise (or very little, and it's not the gurgling everyone talks about), so does'nt this equate to the noise created in a durso being trapped air also?

The setup I desribed before was not a durso, just a regular bulhead in an OFB.

As for anything clogging, you need to make precations for that before it gets to the plumbing no matter what type of steup you have. I have setup many tanks this way and none have overflowed due to something clogging the valve, but I do see your point.

Could you explain how the Durso actually prevent's the noise associated with the drains? I don't think I've ever got the grasp of how they work to be honest with you.

 

[meschaefer]

http://www.dursostandpipes.com/

 

[Psycho graphic]

I've seen that site, it does'nt explain how or why they work though.

As I see it the submerged end obviously does'nt allow for air to enter, therefore it won't allow it into the tubing, but won't the vent allow it to draw air, thus creating noise?

I almost get the idea, I'm just missing one part I think and it's driving me crazy as I usualy can understand things like this.

If you have a perfect balance of return and drain that does'nt allow any air to enter the tubing, why would it make any difference as to how big the vent is?

 

[steveo32]

Meschaefer, my durso runs super quite at first then every 3mins or so it rushes water down. Is that the "flushing" sound your talking about ?> if so I can correct it by making my hole bigger ?

 

[meschaefer]

Meschaefer, my durso runs super quite at first then every 3mins or so it rushes water down. Is that the "flushing" sound your talking about ?> if so I can correct it by making my hole bigger ?

The durso stand pipe page attriubutes this to back pressure, where the overflow empties in the sump. That is the first place to look. If you do not have any back pressure, then you can try increasing the size of the hole.

 

[meschaefer]

I've seen that site, it does'nt explain how or why they work though.

As I see it the submerged end obviously does'nt allow for air to enter, therefore it won't allow it into the tubing, but won't the vent allow it to draw air, thus creating noise?

I almost get the idea, I'm just missing one part I think and it's driving me crazy as I usualy can understand things like this.

If you have a perfect balance of return and drain that does'nt allow any air to enter the tubing, why would it make any difference as to how big the vent is?

In theory, but you are never going to have a perfect balance of return and drain, where the exact amount of water you are pumping into the overflow matches exactly the size of the reutrn line. And if you do, then don't worry about durso stand pipes.

When the water is rushing down the pipe, it creates suction. That suction will pull water out of the return, until the mouth of the pipe is exposed and then it will suck air. It will suck air until the suction brakes, and then water will fill the pipe again. As the pipe fills with water the pressure builds, wich will eventually create more suction. By regulating the hole, you are trying to feed enough air into the system to avoid the suction. If the hole is to small, you create suction, if the hole is to big, you end up pulling to much air into the system wich is also noisy.

 

[Psycho graphic]

Gotcha, and thanks.

I still don't see how this is any better than adding a valve to slightly slow the flow down so there is no air entering, but that is niether here nor there.

As you said it could clog, but I've never had this happen and have used this idea on a few tanks that have run for years without any problems.

Thanks for the explanation.