Why did my Overflow start gurgling?!

[noodleman]

if the pump is overwhelmingly too strong the tank and overflow box will flood...but if it is right at the max gph the water level in overflow box will raise then the durso will form a siphon ( which has a higher flow rate) then the water level will drop, repeat...ie gruggling

 

[noodleman]

mray is always a bit ahead of me in posting :flower:

 

[NYPDFrogman]

I just did a search for the ocean runner 2500 and found it at champion lighting
http://www.championlighting.com/product.php?productid=20840&cat=667&page=1

it's only rated for 630GPH @ 0 head
using head loss calculator available over at reef Central ( closest pump I could get exactly to yours was a mag 7 with similar flow rating)
@ a 4' head using .75" return you only have a flow rate 435GPH
so I think it is safe to say that your pump is not overpowering your drain

here is the link to the calculator
http://www.reefcentral.com/calc/hlc...Couplings=0&CheckValves=0&Exits=1&Entrances=1

humor me check your pump make sure it's clean and your getting good flow from your return

FWIW a 1" drain should handle 750GPH
http://reefcentral.com/calc/drain.php

 

[Domboski]

Fernando, You may be doing this already but make sure you try one thing at a time and start with the easiest tests first. I agree with Frank, your pump is probably not too strong for your tank. I think it's just that you need to make adjustments to the air intake on the durso assuming nothing is clogging your return pump water intake. As mentioned previously, I went through the same thing. It seemed to happen out of nowhere. Once I re-adjusted the intake, the problem went away.

Here is a pic. Sorry about the dirty pipes

 

[NYPDFrogman]

something just dawned on me in an earlier post you said it happens when your lights come on?
is the pump and lights on same circuit?
if so is plugged into a power strip?
try plugging into a separate circuit with the proper size extension cord

 

[fernandokng]

Ok gang here are the few things I've tried:

1. Move the drain pipe above the water to alleviate the back pressure - no change.

2. Vinegar bath of the pump - no change

3. Used a piece of tape to cry to cover the vent hole in the durso (partially, fully) - If I covered it fully, the gushing came even more poweful.

FYI. When I changed the sump, the water chamber of the pump became smaller than before. Perhaps since the chamber is smaller, there is less water surrounding the pump to make the pump more efficient in sending water to the tank? But I doubt this is the issue.

What DID work was partically closing ball valve on the drain side, and that made the water rise higher in the overflow so that it didn't gush into the durso.

Because of the above, do I think it might be the pump not being strong enough. But I never had this issue before, and have been using the pump for over a year.

 

[NYPDFrogman]

Ok gang here are the few things I've tried:

1. Move the drain pipe above the water to alleviate the back pressure - no change.

2. Vinegar bath of the pump - no change

3. Used a piece of tape to cry to cover the vent hole in the durso (partially, fully) - If I covered it fully, the gushing came even more poweful.

FYI. When I changed the sump, the water chamber of the pump became smaller than before. Perhaps since the chamber is smaller, there is less water surrounding the pump to make the pump more efficient in sending water to the tank? But I doubt this is the issue.

What DID work was partically closing ball valve on the drain side, and that made the water rise higher in the overflow so that it didn't gush into the durso.

Because of the above, do I think it might be the pump not being strong enough. But I never had this issue before, and have been using the pump for over a year.

try pluging the pump into a dedicated circuit if you neded an extension cord make sure it's heavy enough
sounds like your pump just isnt pumping the volume if the return area was too small it would get sucked dry

 

[fernandokng]

I plugged it in to a new circut - but no change.

Since the noise went away when closed the drain pipe a little bit, I'm thinking is the pump not being strong enough...

try pluging the pump into a dedicated circuit if you neded an extension cord make sure it's heavy enough
sounds like your pump just isnt pumping the volume if the return area was too small it would get sucked dry

 

[Wes]

Since the noise went away when closed the drain pipe a little bit, I'm thinking is the pump not being strong enough...

the pump not being "strong enough" would not cause gurgling.

 

[MarkF]

I still vote air valve on the Durso

 

[fernandokng]

Mark - Yup. My next step is to use replace the elbow with the T and control the airflow in the intake (thanks for the pics dom!).

 

[Domboski]

No problem. Hopefully you won't have to listen to it anymore!

 

[NYPDFrogman]

the pump not being "strong enough" would not cause gurgling.

yes it would if the overflow box is draining quicker that the pump can refill it than it will flush.
my durso began to make noise I observed the overflow box fill up and drain. every time the water level fell below the elbow it would suck air and make noise.
I noticed that my return from my sump was weak. I replaced my return pump with my spare and the condition went away.
when I disassembled my pump I found a load of calcium build up, unfortunately I could not save the pump.


The fact that he was able to correct the condition by closing his drain, leads me to believe that his pump capacity has diminished.


I would suggest he try a completely different pump maybe someone could loan him one to try or he could simply buy another pump at the very least he'll have a spare pump in case of an emergency.

the ocean runner 2500 he has is around 50.00 online

if you would like I can recreate the condition on my tank and prove that low flow can cause a gurgling sound

 

[fernandokng]

Frank - I might considering getting a back up pump, that is not a bad idea.

Dom - just an fyi, I closed the airhole in my durso, limiting the air, and the gushing became more severe. So the assumption is that I need more air? Either make a bigger hole, so use your airvalve method to allow me to draw in more air? Correct me if I'm wrong here.

 

[NYPDFrogman]

fernandokng
u have a PM

 

[Wes]

yes it would if the overflow box is draining quicker that the pump can refill it than it will flush.

it is impossible for the overflow box to drain quicker than the pump can refill it if set up properly. When using a standpipe like a durso, the overflow box can only drain at the rate that the pump is supplying return water.

With a lower flow you need more air. my quess is lack of air is creating the gurgling. With a low water flow and a low air intake you are creating a vacuum in your drain pipe. The goal is to keep the drainpipe equal to atmospheric pressure.

In this case it is much easier/cheaper to increase the air intake instead of increasing the water volume in the drainpipe.

The fact that he was able to correct the condition by closing his drain, leads me to believe that his pump capacity has diminished.

this backs up my point even further. Closing the drain to reduce water flow also reduces the rate that air needs to enter the pipe to maintain atmospheric pressure.

 

[MarkF]

I second Wes' position - you need to open up the air inlet on the Durso

 

[fernandokng]

Thanks for all the advice gentlemen.

Here is the verdict:

I slightly drilled a bigger hole on top of the durso, and behold, it worked! I guess it needed more air.

It no longers gurgle, and the water in the overflow seems to be at a consistent level (It just weird that I never had the issue before, and the gurgling just appeared out of nowhere).

Regardless, tanks for all the tips!