Overflow "Chugging"

I have a drilled overflow on my 29 gall tank from glass holes. It has a small tube in the bulkhead, I guess to let air in" to let the water flow. The overflow and drain pipe produce alot of noise. It sounds like the overflow is filling up and then all the water shoots down the pipe into my sump. I drilled the air hose hole bigger and inserted a larger diameter tube but this did not help the noise. The overflow water travels down a 1" pvc pipe into a filter sock in my sump. The water is discharged into the filter sock below the water line. I was wondering if anyone had any suggestions as to how I can make the water flow even as opposed to the overflow filling up and making a chugging noise. Should my discharge pipe allow water to pour into the sump from above the water line or under the water line?

 

what does your pipe look like? what style? durso? herbie? etc this will help us help you

 

take a look at this

 

It is a 1' pvc pipe out of my bulkhead, splits off with 1/2" pipe to my refugium with a ball valve, the 1" pvc pipe then continues on into the sump with the end of the pipe being under water. Pretty simple but it sounds like it does not continually flow. Sounds like "chugging" filling up the discharging due to some air problem or the end of the pipe being under water maybe?

 

can you attach a picture of the bulkhead? Where is the tube?

 

There are a couple of potential problems/fixes. Some will drill the air vent hole large enough to acommodate a valve they select. They tap the hole, screw in the air valve and then have the ability to regulate how much air you get. It sounds to me however as if the return pump gph and the overflow gph are out of sync. What is the gph of the return? Add a ball valve to the out of the return pump and play with the flow going out.

 

I had problems similar to yours when my drain was under water. I also had moisture problems when my drain was above water.

I solved all my issues by building a Splash Box.

 

I think unclejed got this one right on the head of the nail

 

No doubt...

However, with a 1" overflow rated at roughly 600 gph in a 29 gallon tank, matching the overflow and return pump rates may not be a practical solution.

 

1+ to Uncle Jed. I think that may be my problem. My overflow is rated at 300gph and I use a mag 7 return pump. I already have a ball valve on the return, maybe I need to adjust it some more. Thanks. And is it best to have water pour into the sump above or below the water line?