How to quiet down a skimmer return?

[Joe Batt]

I have an external skimmer and the feed returns back to my sump.

The return water flow has a lot of bubbles and as such it makes quite a bit of noise.
I thought of a sponge in the pipe but that would end up and a nutrient trap I think.

Any ideas on a solution?

 

[ryeguyy84]

The sponge would also create a potential overflow issue if it got too full of stuff. Ask me how I know that .

You could try adding an elbow at the end of the pipe can aim it towards a wall.

 

[lapin]

I have the same issue. Lot of water = lot of noise. Looks like your return is already under water. That was my first thought as a solution. Mine dumps into a filter sock and I put an extension on it so it was under the water. I have a lot of flow going thru my socks and they all make noise because of the whirlpools they make. I have not played with any other solutions. If you find one let me know.

 

[Taxus812]

What if you ended the pipe onto a block of black filter foam? Then you can just wash the foam once week to get rid of trapped nutrients. The black foam will kill the bubbles and most of the noise. I do that on a much smaller scale with my all in one skimmer outflow.

I think its like $6 at Petco or other stores so it wont hurt to try it.

This stuff just a bigger piece.


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[Crustaceon]

Not sure if you can, but you could put a 90 degree fitting on the end of the outlet tube (may have to make a shorter tube out of pvc), with a few inches of additional tube and have it sit just above the water’s surface. That’ll minimize the “waterfall” effect and cut down on air being injected into the water on exit, causing so much noise.

 

[Joe Batt]

I thought about the sponge, but was worried about blockages affecting the return and causing water overflows upstream.

I have sketched up this plumbing idea, what are your thoughts.

Normal and emergency overflows approx 1 inch below sump waterline. This would keep the water noise inside the plumbing.

The gate valve would be adjusted to restrict the water flow and as such have a build up of water above it so that it was just a little short of the emergency overflow. The emergency overflow would be at a slightly upward angle so that water would not pour down it unless there was a lower blockage.

The air bubbles would disperse in the water column trapped above the gate valve and be vented from the elbow at the top. The water below the gate valve should be air free.

Thoughts and ideas please if it would work?

 

[Crustaceon]

Ever hear an HOB cheapy mechanical filter run? They tend to be really quiet because they have a little chute for the water to gently enter the tank. Keep in mind these outlets are above water level but just barely. I think as long as you have the tubing submerged, you’ll always be fighting the sound of bubbles breaking the surface and containing them could potentially disrupt skimmer flow. The problem I see in the drawing is trying to cancel out the sound of escaping air by allowing it to escape in a different location. It would be like removing the vent tube from a secondary beananimal drain and hearing the open drain underneath it.

 

[Digigill]

I thought about the sponge, but was worried about blockages affecting the return and causing water overflows upstream.

I have sketched up this plumbing idea, what are your thoughts.

Normal and emergency overflows approx 1 inch below sump waterline. This would keep the water noise inside the plumbing.

The gate valve would be adjusted to restrict the water flow and as such have a build up of water above it so that it was just a little short of the emergency overflow. The emergency overflow would be at a slightly upward angle so that water would not pour down it unless there was a lower blockage.

The air bubbles would disperse in the water column trapped above the gate valve and be vented from the elbow at the top. The water below the gate valve should be air free.

Thoughts and ideas please if it would work?

I did something similar and it worked great. In my case instead of the elbow you have at the top I installed a sweeping tee. My pipe is 1 1/2" coming from the skimmer. In the tee outlet adjacent to the inlet I installed a bushing to reduce the pipe size. I selected a size just large enough to handle the water flow. The bushing is followed by a straight pipe which goes down below the water surface in the sump. To this I installed a valve to restrict the flow enough to fill the pipe and only allow a minor amount of water to exit the other outlet of the tee. It would have been better just use 1 1/2" all the way down to the water but I think put this together with some spare plumbing part I had around and it worked so I never changed it.

In the outlet opposite the inlet (emergency pipe) I installed a bushing to reduce the size to 1/2" followed by an elbow and a pipe that just touches the sump water surface. This allows the air to escape easily with the ripple of the surface and the trickle of water still meets the water quietly. The bushing also forces the water to have to rise 1/2" more in the tee before it can exit the emergency pipe which further reduces the turbulent noise.

This is similar to your design except 99%+ of the water never has to free fall in a partially filled pipe and thus very little noise and no added bubbles other than what came from the skimmer. Since the pipe is filled with water and flows more slowly at first and is traveling down, many of the skimmer bubble flow up and exit the emergency pipe. I found that a vent at the top let more noise escape.