Why did my Overflow start gurgling?!

[fernandokng]

God, the noise is driving me insane!

I have a durso stand pipe, and everything has been working well for a few months, noise free.

Recently, I changed to a new sump, and that's when the gurgling started!

See the picture - the water fluctuates in the overflow box constantly, and starts gurgling once it hits the opening at the bottom of the durso (the water before used to be near the top of the elbow).

I really don't understand why it's doing this... is this a return pump issue?

 

[h20 freak]

Check there for an obstruction? Mine did that when I put a filter sponge there and it got full, thats how I could tell it was time to clean the sponge.

 

[fernandokng]

I have no sponge, or any mechanical filters in my tank.

 

[NYPDFrogman]

make sure the hole at the top is clear,
did you change your return pump when you changed your sump?
it's possible that the pump isnt keeping up with the size of the durso.
recently my iwaki went bad and was pumping it's usual capacity and my durso began making noise.

might have to change top cap and start resizing the vent hole
I'm sure KATHYC will chime in

 

[MarkF]

did the placement of the drain line ending inside the sump change? If the opening into the sump is under water there could be a build up of backpressure, then once the level in the overflow rises it causes enough force to overcome the backpressure, the water "flushes down", backpressure builds again and you go through this cycle. Try raising the drain line output so that it is only partially submerged and see if that helps.

 

[MarkF]

Also as mentioned you may need to adjust the size the of the hole in the cap on the durso.

 

[Domboski]

Hopefully Kathy is resting! She works so hard to help all of the members here. In the meantime, here's my take:

I'd try what has already been posted. Something that worked for me a while back was replacing the elbow on my durso pipe with a T. The top of the T was threaded so I can use a PVC plug. It made adjusting the air intake a breeze by tightening or loosening the plug. Once adjusted, I never had to adjust it again. My ears appreciated it!

Let us know how you make out.

 

[fernandokng]

This was my impression at first. I moved the drain above water, but still same issue.

I do notice that most of the gurgling happens when the tank lights are on? :splitspin

did the placement of the drain line ending inside the sump change? If the opening into the sump is under water there could be a build up of backpressure, then once the level in the overflow rises it causes enough force to overcome the backpressure, the water "flushes down", backpressure builds again and you go through this cycle. Try raising the drain line output so that it is only partially submerged and see if that helps.

 

[fernandokng]

What does adjusting the size of the hole do?

Also as mentioned you may need to adjust the size the of the hole in the cap on the durso.

 

[fernandokng]

When I changed my sump, I made the return chamber in the sump smaller... not sure if this would affect it.

make sure the hole at the top is clear,
did you change your return pump when you changed your sump?
it's possible that the pump isnt keeping up with the size of the durso.
recently my iwaki went bad and was pumping it's usual capacity and my durso began making noise.

might have to change top cap and start resizing the vent hole
I'm sure KATHYC will chime in

 

[fernandokng]

Dom, I wish I knew how this looks like... I can't even imagine it :splitspin

Hopefully Kathy is resting! She works so hard to help all of the members here. In the meantime, here's my take:

I'd try what has already been posted. Something that worked for me a while back was replacing the elbow on my durso pipe with a T. The top of the T was threaded so I can use a PVC plug. It made adjusting the air intake a breeze by tightening or loosening the plug. Once adjusted, I never had to adjust it again. My ears appreciated it!

Let us know how you make out.

 

[NYPDFrogman]

When I changed my sump, I made the return chamber in the sump smaller... not sure if this would affect it.

what kind of return pump are you using?
it certainly sounds like the overflow is draining faster than it can be refilled.

Hopefully Kathy is resting! She works so hard to help all of the members here. In the meantime, here's my take:

I'd try what has already been posted. Something that worked for me a while back was replacing the elbow on my durso pipe with a T. The top of the T was threaded so I can use a PVC plug. It made adjusting the air intake a breeze by tightening or loosening the plug. Once adjusted, I never had to adjust it again. My ears appreciated it!

Let us know how you make out.

I do hope that was an acceptable response

 

[fernandokng]

I just tried something that seems to work.

I slightly closed the ball valve on the drain, and the water level rose above the durso hole, so it stopped that sucking.

I don't want to do this long term since the valve can fail... but what does it mean?

Does it mean my return pump is not strong enough? (didn't have issues with it before, not sure why its happening now)

 

[fernandokng]

Frank,

I'm using a Ocean Runner 2500 (700gph at 0 feet). I have a 1 inch drain, and very limited head pressure (I'm using spaflex for both return and drain).

I was looking to get a eheim 1262, but at 950gph, I think it might be too strong, and potential overflow my tank.

what kind of return pump are you using?
it certainly sounds like the overflow is draining faster than it can be refilled.

I do hope that was an acceptable response

 

[NYPDFrogman]

I just tried something that seems to work.

I slightly closed the ball valve on the drain, and the water level rose above the durso hole, so it stopped that sucking.

I don't want to do this long term since the valve can fail... but what does it mean?

Does it mean my return pump is not strong enough? (didn't have issues with it before, not sure why its happening now)

is it an external or submersible pump?
might want to take the pump apart and clean it
calcium has a habit of building up in pumps reducing it's performance,
it it's a submersible see if there is sponge prefilter

 

[fernandokng]

Yeah, it's a submersible one. I'll try some vinegar tomorrow, and keep you guys updated.

Thanks gang.

 

[mray]

I think that your drain is not fast enough for the return. You have a gurgling sound because the hole on your durso is too large. Try covering part of it and see if it stops after awhile.

 

[noodleman]

i think your pump is too strong for your drain, 700gph with all the head lost is about 600gph give or take and thats the max your drain can handle.

 

[NYPDFrogman]

http://reefcentral.com/calc/drain.php

I am under the assumption that prior to your new sump this worked OK?
I may be wrong here but if the pump was too strong it would overflow the skimmer box and tank?

I think in an earlier response I addressed the vent hole

 

[mray]

It wouldn't overflow because once the water level has reached a certain level it would create a siphon therefore increasing the flow rate down to the sump and then breaking siphon once it has equalized and the end result is the gurgling sound you hear.