Help Quiet Down My Overflow!

[Keith P]

I'm going nuts with the tanks overflow. It's an Oceanic Tech 70. I've tried both a stock man pipe and a durso.

I get a combo of gurgling in the plumbing and a water spilling sound from the internal overflow box.

I found the only way to reduce the gurgling is to close my return line's ball valve by 2/3 or more. I am running a 1300GPH pump. I have the 3/4" return, 1/2" line bypassing back to the sump, and a 1/2" line going to the chiller. The two 1/2" lines are wide open.

I've tried fooling the depth of the drain exit. It's currently 1-2" submersed in a filter sock.

Maybe I over sized the pump? Maybe running 2/3 closed is what this setup needs? How do I figure out my return GPH? I assume I will need to hook the over flow to a bucket or something...

The water spilling sound is my new demon. I had to lower the durso (or stand pipe) to put the cover on the tank and overflow box. Closing the return valve helps considerably in this department too.

Did I simply over size my pump, or am I missing something??

Another note worthy observation. My tank is not level. I will fix this when I get someone with muscles to come over :flirt: :biggrin: Can this be part of the cause?

 

[motortrendz]

this was posted on another thread:
by mk4fan
http://www.reefcentral.com/forums/sh...d.php?t=344892

i thought it was awsome and i got alot of info out of it, hope it helps

 

[Keith P]

Please try the link again.

 

[motortrendz]

http://www.reefcentral.com/forums/showthread.php?t=344892

sorry

 

[JaMan]

I removed a loud durso and placed a piece of egg crate over the 1.5" drain hole to act as a screen. I then filled the overflow with bio-balls. The over flow has over 2,000 gph of flow and is dead silent!

 

[motortrendz]

interesting..how are your nitrate levels??

 

[Keith P]

interesting..how are your nitrate levels??

I see where you are going with this... Don't even bother :tired:

 

[Wes]

I see where you are going with this... Don't even bother :tired:

It's a valid question because removing the standpipe and filling with bioballs essentially turns the overflow into a wet/dry aka nitrate factory.



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[fritz]

Interesting and if your nitrate levels are indeed low, really interesting.

The trick to making your overflow quiet is to address the cause of the noise:

1. don't allow the water to drop a long distance
2. do not push more water than you need through the overflow.

Lots of people use their return like it's a circ pump and then complain around this time of year about heat and electric use. I use circulation pumps to circulate and a return pump to move just the amount of water I need from the sump to the main tank. I judge this amount by my skimmer. If my skimmer can process only X amount of water an hour why push 20X or 100X past my skimmer, through my sump and back to the tank? It makes no sense. I also usually mess with a fuge and that needs hardly any flow.

My favorite setup is to gravity feed my skimmer. It makes the MOST use out of the most underused equipment in our tanks, the overflow. Gravity feeding dumps that surface protein straight into the skimmer where it can be...dealt with. The extra spillover then feeds a fuge that raw funky water that fuges love so much. My return then pumps this amount of water back to the tank.

By starting with a low (and proper) amount of flow you don't have the "it sounds like Niagra Falls" because it isn't Niagra falls, it's a small creek. Second, by slowing the water or better yet not letting it fall at all but rather run down a hill you completely remove the "Falls" part of the noise from the equation.

 

[fritz]

It's a valid question because removing the standpipe and filling with bioballs essentially turns the overflow into a wet/dry aka nitrate factory.



Sent from my iPhone using Reefs

Wes!!!

Speaking of people who know how to properly size their return pump! :hug:

 

[18oreefer]

your pump is actually undersized. the reason you are getting noise is because your pump isnt filling your overflow box fast enough, and thats the reason why when you close the valve on your drain line it gets quieter. with the flow restricted on the drain line you now match the flow coming back to the tank. i have valves that are closed a bit on both my drain lines, and my tank is quiet. a mag 18 should get you to the point where you only have to close the valve a little bit to match not 2/3 closed.

 

[fritz]

When I bought my house there was a spot in the basement where water was seeping in from the outside. It had worn away the mortar in the foundation and there were a few spots where water would come through during a hard rain. The old owners had tried foam, drylock, cement and a few other solutions to address this concern.

The first time it rained I went outside and found that the gutter just above that spot was dipped down a bit and thus all the water from that side of the house would dump just above this spot. That is what was causing the water to seep in. I had someone re-nail the gutters and cemented the crack in the driveway. My basement has been bone dry every since.

My point is why not address the cause of the problem rather than come up with fifteen fixes for it? The overflows are already oversized. Who needs 750GPH going through their sump? Really what are you doing down there?

The loud noise caused by overflows is usually due to someone who went WAY too big on their return pump and has an overflow with a five foot drop that dumps 700GPH. If you've ever seen 700GPH fall five feet anywhere in the world, it was loud.

 

[Wes]

Wes!!!

Speaking of people who know how to properly size their return pump! :hug:

:shhh: the pump on the new tank is a monster. overcompensation for the large head. And yes the overflows are noisy but they are in the garage.

 

[Wes]

your pump is actually undersized. the reason you are getting noise is because your pump isnt filling your overflow box fast enough, and thats the reason why when you close the valve on your drain line it gets quieter. with the flow restricted on the drain line you now match the flow coming back to the tank. i have valves that are closed a bit on both my drain lines, and my tank is quiet. a mag 18 should get you to the point where you only have to close the valve a little bit to match not 2/3 closed.

im sorry but this is absolutely false.

the lower the return flow, the quieter the overflows are.

A) There is no such thing as "not filling the overflow box fast enough". The standpipe will only drain at the rate the water is being pumped. It's impossible to drain faster than you can fill the overflow when using a standpipe.

B) The reason it gets quiet when you slightly close the valve is you are allowing the air to escape before it falls into the sump. This happens no matter how much you are pumping. This is dangerous if you do not have a secondary emergency drain because the slightly closed valve is prone to clogging.

 

[18oreefer]

im sorry but this is absolutely false.

the lower the return flow, the quieter the overflows are.

A) There is no such thing as "not filling the overflow box fast enough". The standpipe will only drain at the rate the water is being pumped. It's impossible to drain faster than you can fill the overflow when using a standpipe.

B) The reason it gets quiet when you slightly close the valve is you are allowing the air to escape before it falls into the sump. This happens no matter how much you are pumping. This is dangerous if you do not have a secondary emergency drain because the slightly closed valve is prone to clogging.

I respectfully disagree. What happens when you turn off your pump? All the water drains down. Before its all gone it gets really noisy. You are not providing a high enough level in the tank to push enough water over the box. What happens when you close the line down with a valve you restrict the flow to the sump. When you restrict the flow the box no longer needs as much flow and you are able to match what is going into the box with what is going out. Plane and simple water is moving out of the box faster than it can be filled up. If you have more gph then the box can be filled faster and the noise will go away because the water level isnt dropping below the drains. The only thing air does is when the level falls low enough for air to be sucked in it slows the rate the water is being sucked in because the air is taking up space that water should be. Now that air is being sucked in flow out of the box is less, and this gives the flow into the box a bit to catch up. Once it does catch up the slurp goes away until the drain brings the level back down again. Now if its not slurping and the level is low in the box you will have the water fall noise. All you have to do is restrict the drain from the box and it will bring up the level in the box. If you dont believe me try a little experiment on your own tank. Valve down your return pump. See if the noise gets worse or better. Now valve down your overflow drains to see if the noise gets better or worse. Please try the experiment and you will have your answer. Ok im done.

 

[Keith P]

I respectfully disagree. What happens when you turn off your pump? All the water drains down. Before its all gone it gets really noisy.

The noise is the sound of water and air back feeding through the return lines, not the drain.

The only thing air does is when the level falls low enough for air to be sucked in it slows the rate the water is being sucked in because the air is taking up space that water should be. Now that air is being sucked in flow out of the box is less, and this gives the flow into the box a bit to catch up. Once it does catch up the slurp goes away until the drain brings the level back down again. Now if its not slurping and the level is low in the box you will have the water fall noise. All you have to do is restrict the drain from the box and it will bring up the level in the box. If you dont believe me try a little experiment on your own tank. Valve down your return pump. See if the noise gets worse or better. Now valve down your overflow drains to see if the noise gets better or worse. Please try the experiment and you will have your answer. Ok im done.

Restricting the drain is asking for a flood and generally not advisable.

I'm in the same boat with my over flow. I have restricted the return, thus slowing down the flow, but still have a lot of gurgling.

 

[juiceguy]

I think you answered your own question when you said that you valved down your return pump and it quieted down the oveflow. to much flow produces a cascading waterfall in your overflow and then your durso or stockman has to drain faster, drawing in more air as more water is drained.

i have the same issue because of the sea swirls, when they turn towards the overflow they push more water in and force the drains to draw in more air.

 

[18oreefer]

Keith, the drains make the noise before you hear all of the air gurgling of the air in the lines.


Open your pump all the way, put a piece of tape over the air tube on the top of your drain, adjust your drain line valve and you should be nice and quiet. If your still not quiet try valving down your 1/2" line to the sump then the chiller if necessary. Its a matter of balancing flow in and out of your tank. And your noe of the tank was easly over looked at the bottom of the pics. It could play a roll if the back of the tank is on the high side.

 

[Wes]

Keith, the drains make the noise before you hear all of the air gurgling of the air in the lines.


Open your pump all the way, put a piece of tape over the air tube on the top of your drain, adjust your drain line valve and you should be nice and quiet. If your still not quiet try valving down your 1/2" line to the sump then the chiller if necessary. Its a matter of balancing flow in and out of your tank. And your noe of the tank was easly over looked at the bottom of the pics. It could play a roll if the back of the tank is on the high side.

What this does is create a syphon. It's more quiet because you are keeping air out of the drain. This is quieter than a standpipe at atmospheric pressure but it is not safe and you are asking for a flood.

It is not how these overflows are designed, this advice leads to wet floors.

Water is supposed to fall down the drain as if flows into the overflow.

Some people use the syphon method by restricting the drain because it is quiet...but they also have a emergency standpipe plumbed slightly above the water level in the overflow because eventually the restricted drain clogs.

If you plan on using the standpipe as designed and not a makeshift syphon, less flow going down the drain makes it quiet.

ps: water does not move out of the box faster than it can fill up. Think about it. It's impossible. If that were true the overflow would be empty. The water level will never drop below the drain unless you have a leak somewhere.

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[Keith P]

And your noe of the tank was easly over looked at the bottom of the pics.

noe?