I really need help. (Hopefully with a Herbie style drain)

[rocketlily]

I am not having any luck with trying to do plumbing. The tank is 90 gal and I have an over flow compartment in which I have built a durso. The noise of the water entering the sump is unbearable. Something like running a bathtub. Massive air bubbles and alot of noise. It has nothing to do with the holes in the cap, as it doesn't make any difference whether the cap is on the durso or not. I am also getting alot of fluctuating height in the water in the overflow, up and down. Not to the point where it sounds like a toilet flushing, but it rises and lowers.

The tank is in the living room and I really need to try to make it quiet. Any help would be very much appreciated.

Thanks

[Ya Dude]

try reducing flow of main pump with a ball valve sounds like its too much.I had same problem.

[Phanman]

on top of the durso... do you have a hose for air to get in? try adjusting the hose up or down to let the right air mixture in.

[silverplanet]

how far does the water fall in the overflow? what is the sump and tank return plumbing size? is ther a air hose in the durso top?

Jason

[sphelps]

You may need a larger standpipe. Also the drain should be one size smaller than the standpipe, for example if standpipe is 1.5" drain to sump should be 1.25".
Does the overflow drain line go straight down into the sump? It sometimes helps to run a section of the drain line horizontal to slow it down.

Do you have dual drains in the overflow? Or just the one? What size? It can be really hard to have both a high return flow rate and very quiet operation with a single drain setup.

[rocketlily]

"on top of the durso... do you have a hose for air to get in? try adjusting the hose up or down to let the right air mixture in"
On top of the durso is a cap with 8 - 1/16" holes that I can cover/uncover.

"how far does the water fall in the overflow? what is the sump and tank return plumbing size? is ther a air hose in the durso top?"
Tank height is 20" and water in the overflow is 17" with a 20" drop to the top of the sump.

"You may need a larger standpipe. Also the drain should be one size smaller than the standpipe, for example if standpipe is 1.5" drain to sump should be 1.25".
Does the overflow drain line go straight down into the sump? It sometimes helps to run a section of the drain line horizontal to slow it down"
Standpipe is 1.5" and drain is 1.5" with 2 - 45's. Would not reducing the drain size force the water out faster?

[Hairytank]

Just to be certain where the noise is coming from...according to your post it sounds like your noise is coming from your sump and not the overflow..is this correct?
ie: when you stick your head in the stand over the sump..the sound is coming from there and not from above...?

Some possible solutions if it is the water entering the sump that is causing the noise.
If the end of the plumbing for the water to enter into the sump is submerged too much then there will be backpressure and it is more difficult for the air to get out until pressure builds up and then large bubbles will be forced out relieving the pressure until it builds again. This will cause fluctuations in your water as once the built up bubbles escape then the water flows better, lowering the water level.
A couple of solutions for this one, angle the pvc entering the sump and have it no more than 1-2" below the surface. If the plumbing is perpendicular (90 degree angle) to the water then it is harder for the air to be released. I would also add a filter sock to the plumbing entering the sump and this will break the bubbles up some and help reduce noise and bubbles in the sump. Besides a filter sock if maintained properly will polish your water nicely.

[sphelps]

Originally Posted by rocketlily

Would not reducing the drain size force the water out faster?

Only if pressure exists, the water will fail due to gravity so unless the pipe is full velocity may actually decrease due to pipe wall friction. But the main purpose is to stop the air from entering the drain and stay in the standpipe exiting through the vent hole(s). Running a horizontal section will also help, it will slow the flow and cause the pipes to flood better again keeping air in the standpipe not the sump. It really sounds like you would benefit from a Herbie style overflow, but I'm guessing you only have the one drain?

[rocketlily]

Originally Posted by Hairytank

Just to be certain where the noise is coming from...according to your post it sounds like your noise is coming from your sump and not the overflow..is this correct?
ie: when you stick your head in the stand over the sump..the sound is coming from there and not from above...?

Some possible solutions if it is the water entering the sump that is causing the noise.
If the end of the plumbing for the water to enter into the sump is submerged too much then there will be backpressure and it is more difficult for the air to get out until pressure builds up and then large bubbles will be forced out relieving the pressure until it builds again. This will cause fluctuations in your water as once the built up bubbles escape then the water flows better, lowering the water level.
A couple of solutions for this one, angle the pvc entering the sump and have it no more than 1-2" below the surface. If the plumbing is perpendicular (90 degree angle) to the water then it is harder for the air to be released. I would also add a filter sock to the plumbing entering the sump and this will break the bubbles up some and help reduce noise and bubbles in the sump. Besides a filter sock if maintained properly will polish your water nicely.

The noise is from the water entering the sump. There are a great amount of large bubbles with the water. I was also thinking that the backpressure was the cause of the fluctuating water level, but I was hoping for a different solution as the sump would need to be changed to allow for a different angle of entry.

"But the main purpose is to stop the air from entering the drain and stay in the standpipe exiting through the vent hole(s). Running a horizontal section will also help, it will slow the flow and cause the pipes to flood better again keeping air in the standpipe not the sump. It really sounds like you would benefit from a Herbie style overflow, but I'm guessing you only have the one drain?"
I agree that it is probably the air coming through with the water causing the noise. The drain is right above the inlet to the sump so not enough room for a horizontal section unless I change the inlet to the sump to another corner. Yes you're right, only one drain.

[mark]

the rising and lowering in the overflow indicates that the Durso is not tuned and would be getting some surging of air.

The negative with the Durso though is you'll always get air in the line back to the sump (not with a Herbie).