Quieting a Drilled Overflow

[Nate92]

Hello,

I am in the process of setting up my first fish tank. The setup (80G display, 30G sump, skimmer, powerhead, etc.) is up and running smoothly. However, my drilled overflow is incredibly noisy. It sounds like it's constantly bubbling (almost like someone is slurping a drink around the clock!). I included pictures below. When I plug the top hole on the "overflow piece" (not sure of the correct word) with my finger, the sound does go away. However, that hole is obviously included in the piece for a reason. Any tips or suggestions on how to reduce the noise would be much appreciated! Thank you!

-Nate

 

[Bharathshankar]

Just put an airline tube with a check valve.

 

[Nate92]

Just put an airline tube with a check valve.

Thanks for your response- could you clarify what you mean by that? I'm new to the hobby. Would you suggest putting an airline tube into the top hole? what specifically is a check valve? If I were to put an airline tube in, would that impede at all with the water flowing down to my sump? Thanks again!

 

[Erica-Renee]

Are those just pipes at the top of the tank with plumbing running down into the sump.. If so there is not much you can do other then reduce flow and Adjust how deep or not the drains are into the sump. To get it really Quiet and proper surface skimming you will need a weir around them with the pipes turned under the water ..

I hope this helps . its not as complicated as it sounds..

 

[Nate92]

Are those just pipes at the top of the tank with plumbing running down into the sump.. If so there is not much you can do other then reduce flow and Adjust how deep or not the drains are into the sump. To get it really Quiet and proper surface skimming you will need a weir around them with the pipes turned under the water ..

I hope this helps . its not as complicated as it sounds..

Hi, Erica-Renee. Thanks for your response. Those pipes at the top of the tank are running directly down into the sump. The sounds aren't coming from the sump though- they seem to be coming from the display part of the tank where the water actually starts to flow down. The first chamber of the sump where the water enters is relatively quiet. The culprit of the noise seems to be the top, small, hole on the black piece in the picture...

 

[rknott]

I didn't ever see an answer here on what is wrong with plugging the holes at the top. I am experiencing this same thing and I am going to close those holes at the top. I tested and my tank wont over flow even if down line is stopped because I run out of water first AND I have plenty of water flowing when it is closed. I see no reason not to close them.

 

[Pntbll687]

I didn't ever see an answer here on what is wrong with plugging the holes at the top. I am experiencing this same thing and I am going to close those holes at the top. I tested and my tank wont over flow even if down line is stopped because I run out of water first AND I have plenty of water flowing when it is closed. I see no reason not to close them.

Plugging the hole would create a full siphon drain. The water would rush to the sump until air enters the pipe. Then you would wait until the water pressure forces the air out of the pipe, creating a toilet flush sounds.

You can add a gate valve the the siphon to regulate flow into the sump. It is not recommended to do this if you only have a single drain pipe. You increase the risk of clog in the pipe by restricting it with the gate valve.

Op,

Your current situation is probably caused by a return pump that is over powered in terms of gph in compared to what the drain can handle. If the return pump is adjustable, just turn it down, if not, making the hole slightly larger may help.

 

[rknott]

Plugging the hole would create a full siphon drain. The water would rush to the sump until air enters the pipe. Then you would wait until the water pressure forces the air out of the pipe, creating a toilet flush sounds.

You can add a gate valve the the siphon to regulate flow into the sump. It is not recommended to do this if you only have a single drain pipe. You increase the risk of clog in the pipe by restricting it with the gate valve.

Op,

Your current situation is probably caused by a return pump that is over powered in terms of gph in compared to what the drain can handle. If the return pump is adjustable, just turn it down, if not, making the hole slightly larger may help.

This is helping, but I am still not there yet. I have a DC pump and I cranked it all the way down to 3 out of 10 and still noisy. Minimal flow. I didn't mention earlier I do have a valve that I closed just slightly, that my local store recommended I buy. With that closed slightly still some noise, but less. Then plug the hole and totally quiet.

It seems like a full siphon drain is a good thing because it gets the air out of the line. I am not seeing the downside here. You say not recommended because you increase the risk of a clog. Even if I did get a clog, seems unlikely given it is just very slightly closed, I won't flood the house because I will run out of water first. With that in mind, I can't see the risk. Apologies if I am being dumb and making you repeat something you already answered.

 

[Pntbll687]

This is helping, but I am still not there yet. I have a DC pump and I cranked it all the way down to 3 out of 10 and still noisy. Minimal flow. I didn't mention earlier I do have a valve that I closed just slightly, that my local store recommended I buy. With that closed slightly still some noise, but less. Then plug the hole and totally quiet.

It seems like a full siphon drain is a good thing because it gets the air out of the line. I am not seeing the downside here. You say not recommended because you increase the risk of a clog. Even if I did get a clog, seems unlikely given it is just very slightly closed, I won't flood the house because I will run out of water first. With that in mind, I can't see the risk. Apologies if I am being dumb and making you repeat something you already answered.

As long as you're comfortable running it that way then go for it.

One thing to watch it for of flooding after a power outage. It can take longer for the siphon to stabilize, and people have floods because the return keeps popping water but nothing is going back down. That's why every overflow design that uses a full siphon also has an emergency drain that is as big or bigger than the pipe for the siphon.

 

[lapin]

So the hole is sucking air. This causes noise as the water and air mix and go down the pipe. You plug the hole and the noise goes away. I believe the reason the hole is there is because in a power outage your pipe will allow the tank to drain down until the drain pipe sucks in air. Having the hole allows breaks the siphon so less water drains into the sump, preventing an overflow of your sump.
Normally that strainer would be pointed down.
What you want is to have the hole covered with water to create a full siphon. (raise water level in the tank or overflow box if you have one) You can either turn up your pump speed or fine tune the drain by having a valve on the pipe that flows into the sump.
This is my opinion by looking at your picture and not seeing the full set up.