Would Drilling a few holes in my Overflow line help bubbles?

My return line from the overflow is making quite the ruckus with all of its bubbles in the sump. While I do have the top of it drilled with a breather hose, it doesnt seem to be enough.
So Im asking, if I drilled a few 1/4 inch holes in my overflow line just below the waters surface in my sump would that help me with bubbles and noise?

 

can you adjust the breather hose up or down? maybe a slightly longer piece of hose? maybe a little lager size hose? I would say no to drilling holes..... can you take a pic so we can see what you are talking about?

 

its about every 5 seconds that one large gurgling bubble will come out of the bottom.. its kind of obnoxious and was looking for a fix..
The vent pipe is about 12 inches long and moving it up and down does a little but not much..

The drain pipe..

pipe submerged in sump

flowing pipe in sump..

 

that is out of the back of your tank? I'd hate for you to mess with it near that bulkhead. don't want to unseat that...... hmmm try putting in a tube that is about 3" long and letting about half of it sticking out and the other half submerged. see how that works...

 

Sure is a shame that Tangster isn't around to field this question. He helped me when I had the same issue. The thing is, the return has to be vented enough so that suction doesn't become an issue. I think that's your problem.

I'm not sure your setup is fixable. A properly constructed standpipe vented at the top is the standard fix for gurgling issues such as yours. Thing is, a standpipe is constructed inside an overflow box. Do you have an overflow box inside the tank to correspond with that 90 outside the tank?

And just to clarify here, that is where water is leaving the DT, not entering it, right?

 

Yes, thats coming through a 1.5" bulkhead. I can try to move the tube up, I just hate messing with it too much..

yes there is a slim overflow inside my DT which has a baffle inside it to keep some of the suction down.
and yes, this is the drain line from my DT

 

I guess your only option is to make that vent hole larger then. You'd have to stick a suitable sized tube into the hole you make to keep it floodproof. That's a tough one. :-/

 

I had the same problem with my tank, to fix it I had to vent the overflow line by changing the 90 out for a tee and then adding a small length of pipe to it to stop any possible water spilling out the top of the "t". However I don't know what stage your tank is at? Can you drain it down enough to change the 90 for a "t"?

 

I could certainly try that, I am just setting up my tank so I can take the water back out.. My problem is where would I find a threaded 1 1/2" tee?

 

Im going to try this.. I guess I should just drill about a 1/4" hole and stuff some tubing in it to see if that helps..