Burping overflow driving me nuts

[Jason McK]

I have a 75G AGA with the "twin overflow" plus the derso styled AGA Mod. I have just rebuilt my sump to accommodate a new skimmer and hard plumbed the overflow tube with PVC. The overflow goes strait to the bottom of the sump and there is one 45 elbow at the end. Now I am able to increase the flow through the overflow but the more water running through the louder and more frequent the "Burping" sound becomes.
I have tried adding a flex airline tube down the overflow pipe but this does not seam to help unless I need a bigger tube or if I need to find the sweat spot.

Any help would be great

Thanks
Jason

[bluetang]

I had the same problem. My fix was to place a ball valve where the water reaches the sump and turn it back a notch. Then I created a small stand out of milk crate and places cotton in from of this return to quite it even more.

Is your return underwater?

[sumpfinfishe]

I had to do pretty much the same as Bluetang, I run a mag3 on a 27gl and I was getting a siphone as water was drawing too fast into the sump from the overflow which caused a slight backup which led to a loud flushing noise everytime the intake line drained into the sump. To improve this problem(5 years ago) I also installed a ball valve on the intake line half way down before it reaches the sump. I simply turned the valve back slightly to create a full intake line, and now no flushing and no my overflow does not backup.
I had this problem due to two reasons, one my intake to the sump feeds directly underwater into the sump wich created a flush effect and also because I used a 3/4 bulkhead instead of a 1" fitting. Live and learn

Goodluck

[Jason McK]

OK let me run this by everyone as you can tell me if I'm nuts.

I have the AGA "Mega" overflow. The one that is just a really expensive version of a derso.
The biggest difference between the Durso and the AGA is the the Derso recommends that the overflow pipe is reduced just above the bulk head.
So in my case I should have a 1 1/4" PVC intake that drains through a 1" bulk head.
I currently, with the AGA have a straight 1" drain.

Do you think modifying the AGA would help with the burping? Because the water would slow at the reduced pipe and have time to release any air?

J

[pinhead]

This is a simple solution that worked for me.


The burping is due to a bubble of air coming up while the water is going down a small opening. This is much like the "glug glug" you get when pouring a glass of wine - it stops when the bottle is half full and the air can flow in while the wine is flowing out. If you look at a bathtub, the water spirals down the drain.

If you can mimic the spiraling, you can get rid of the burping. I did this by getting a thin plastic hose and putting it over the overflow. It was a thin white plastic piece rather than the clear hoses. By cutting the top at an angle at about 6 places and bending them in it sort of looked like a kids pinwheel. The water spiraled in like the bathtub and the burping stopped.