Another Overflow Noise Thread

Mole · Feb 14, 2014

Ok, so I have my 65 gallon reef ready up and running. It's still cycling and I'm trying to tune the overflow to be quieter. It came with a durso overflow which is about 1 1/2" in diameter which goes through a 1" bulkhead. I plumbed from the bulkhead to the sump using 1" sch40 pvc. I'm running a mag 9.5 through 3/4" shc40 pvc through the 3/4" return bulkhead and split to two 1/2" loc lines. I did the math for the rise of the plumbing and I should wind uf with about 350gph of flow at head height of 4' (turnover rate of 5.38 times/ hr). I've tried both the durso that came with it and a "hofer" gurgle buster (worked great on my external overflow).

My problem is, when I have the return valve full open and the overflow valve full open, it seems that the overflow fills and then dumps creating a tremendous amount of turbulence and noise in the sump (think capping one end of a tube, filling it with water then immediately removing the cap. If I open the overflow valve and close the return until it stops dumping the water in the overflow (read as returning water to the tank at the same rate of speed with which it flow out) then the constant running water noise of the water going into the overflow drives me crazy. Am I just not there yet and I need to close both valves better so they mesh? Do I need to go with bigger overflow tubing from the bulkhead? Or am I missing something altogether?

Help me out here please.

KorL · Feb 15, 2014

How about raising the durso stand pipe

legendary · Feb 15, 2014

I had a similar problem like this and the solution to mine was the hosing underneath going to the sump had some slack in it, creating a pocket. See if that is your case as well, if so just make it where your hose has a constant downward slope into the sump. Hope this helps!

Mole · Feb 15, 2014

All the dump is going straight down into the sump. I'm thinking that if I put a 45 between the bullhead and the exit for the dump, the air will exit easier resulting in a loss of noise. Headed to home Depot anyway today so it's worth a shot. Had a bit of an emergency situation yesterday with the tank anyway so the trip is a necessity.

jayhawk · Feb 15, 2014

This should help. You will need air pump tubing (standard size for an aquarium air pump) and a rubber o-ring. The o-ring should be the diameter of the tube. Take off the end cap that sits on top of the durso. Drill a hole in the center of the end cap. The hole should be small enough to where the tube will not slide through. There should be some resistance. I found that a "step" drill bit works best. Place the end cap back on the durso. Turn on the tank return pump. Cut the tube about six to seven inches. Feed the tube into the hole in the end cap. You will immediately hear a difference. Make adjustments until you are satisfied. Mark the tube where it exists the hole. Place the rubber o-ring on the mark and reinsert the tube. The o-ring ensures that the tube stays in place. Cut the tubing about a half inch from the o-ring. You don't want excess hose sticking out of the top of the durso end cap. A filter sock at the exit of the overflow will also deaden some sound. Hope this helps. It helped me.

Mole · Feb 16, 2014

jayhawk said:
This should help. You will need air pump tubing (standard size for an aquarium air pump) and a rubber o-ring. The o-ring should be the diameter of the tube. Take off the end cap that sits on top of the durso. Drill a hole in the center of the end cap. The hole should be small enough to where the tube will not slide through. There should be some resistance. I found that a "step" drill bit works best. Place the end cap back on the durso. Turn on the tank return pump. Cut the tube about six to seven inches. Feed the tube into the hole in the end cap. You will immediately hear a difference. Make adjustments until you are satisfied. Mark the tube where it exists the hole. Place the rubber o-ring on the mark and reinsert the tube. The o-ring ensures that the tube stays in place. Cut the tubing about a half inch from the o-ring. You don't want excess hose sticking out of the top of the durso end cap. A filter sock at the exit of the overflow will also deaden some sound. Hope this helps. It helped me.

Tried this already too. Will be trying a couple more things over the next few days.