Plumbing and Noise question

[joe-ejs]

Hello, I am hoping to get some clarification on my overflow and return line plumbing. I purchased this tank used, so I inherited the plumbing as is. As you can see in the picture below, I have a corner overflow on my 90gl. Overflow has a little air hole at the top and there is also a 1/2" hole on the side of the overflow pipe as well. You can see this in the 2nd picture. All works well.

The return line is the PVC with the 90 degree elbow at the top. The underside of this 90 degree elbow is where the noise is coming from as well as my question. There is a little 3/8" or so sized hole under that 90 which is gurgling and causing noise. If I cover that hole with my finger, 80% of the noise goes away. I assume that is a 2nd backup to break siphon, but am not sure.

Do I really need that siphon break on that pipe since I also have one on the overflow? I assume if my return pump stops, the water level will drop to the level of the larger hold on the side of the overflow line....is that correct?

Thanks for any input...

 

[Sean Clark]

Do you have a valve on the drain line below the tank? If so you just need to tune it a little bit to silence the drain. My guess from how you described the situation above would be that you need to restrict the drain.

 

[joe-ejs]

Do you have a valve on the drain line below the tank? If so you just need to tune it a little bit to silence the drain. My guess from how you described the situation above would be that you need to restrict the drain.

Hi Sean, I do have a valve on the drain line. But the noise is coming from the return line, which is the pipe on the right side in the picture, which has a airhole underneath that 90 degree fitting. Will adjusting the overflow cause the noise from the return to reduce?

 

[Sean Clark]

Ok sorry, I misunderstood. That hole is likely an anit-syphon hole to allow air in in the event of a power outage or pump failure. You could cover it or patch it completely and move it to outside the weir. Possibly on the bottom of the loc-line so it is still below the normal running waterline.

 

[Eagle_Steve]

Hi Sean, I do have a valve on the drain line. But the noise is coming from the return line, which is the pipe on the right side in the picture, which has a airhole underneath that 90 degree fitting. Will adjusting the overflow cause the noise from the return to reduce?

Looks like they made a siphon break. Quite a large one at that. The purpose of it is to suck air as soon as the retunr shuts off and the water level reaches that hole. This prevents large amounts of water from draining back in the event of a pump/power failure.

I would suggest you replace that 90 or plug the hole. You can then drill a small 1/16" or 3/32" hole on the underside of the 90 right where the lock line fitting screws in. This will provide a small silent siphon break, as opposed to a large hole where the return water is rushing out of. The trick is to have the hole pointing straight down and just below the waterline, so the flow that does come out of the hole has a long distance to travel before hitting something, but is slightly under the water, so you do not hear splashing.

 

[Eagle_Steve]

It just clicked that you said you have a valve on the drain. If this is the only drain, that is not a good thing. Over time, crud will slow the flow and you risk the DT overflowing.

I would suggest you open the valve all of the way and then tune the durso drain via making the air hole in the top smaller or larger. If the hole is large for example, it will allow more air and less of a siphon will occur. Smaller hole allows more siphon. You can also fit a larger air line valve to the hole and adjust the valve to allow more or less air in. This is much easier and will allow for a fine tune to keep the overflow almost silent.

 

[Freenow54]

Hard to tell from the pictures I will clarify one thing. You seem to have the same tank as I do. The supply pipe of water back to the Aquarium " that is the clarification " does not have a hole in it on mine. My elbow is actually out of the water to the bottom of the fitting. I had to cut that pipe originally. and where your hole is would be below the water in mine. I would say you do not need it. It is odd that it gurgles as that would be positive pressure. Maybe it is acting like a venturi, and actually sucking water in

 

[Freenow54]

Ok sorry, I misunderstood. That hole is likely an anit-syphon hole to allow air in in the event of a power outage or pump failure. You could cover it or patch it completely and move it to outside the weir. Possibly on the bottom of the loc-line so it is still below the normal running waterline.

Your anti siphon is on the drain

 

[joe-ejs]

Looks like they made a siphon break. Quite a large one at that. The purpose of it is to suck air as soon as the retunr shuts off and the water level reaches that hole. This prevents large amounts of water from draining back in the event of a pump/power failure.

I would suggest you replace that 90 or plug the hole. You can then drill a small 1/16" or 3/32" hole on the underside of the 90 right where the lock line fitting screws in. This will provide a small silent siphon break, as opposed to a large hole where the return water is rushing out of. The trick is to have the hole pointing straight down and just below the waterline, so the flow that does come out of the hole has a long distance to travel before hitting something, but is slightly under the water, so you do not hear splashing.

Thanks Sean,

I am going to try your suggestions and see what happens. Hopefully I can remove that 90 fitting from the standpoint. I hope the previous owner didn't glue it...then I can try a few different holes and see what works the best. Like you said, that hole is above the water line which is causing the noise...If I could adjust the overflow standpipe up 1/4" that would also fix the issue...I think...

 

[Sean Clark]

Your anti siphon is on the drain

Anti-siphon is on the return. I had them mixed up in the earlier post. Thanks.

 

[Sean Clark]

You can also eliminate the hole all together and run you return nozzle fitting as high as you can. That way when the water goes below the return nozzle it will suck air in and brake the siphon. This limits your return flow direction a lot though.

 

[Dburr1014]

Hello, I am hoping to get some clarification on my overflow and return line plumbing. I purchased this tank used, so I inherited the plumbing as is. As you can see in the picture below, I have a corner overflow on my 90gl. Overflow has a little air hole at the top and there is also a 1/2" hole on the side of the overflow pipe as well. You can see this in the 2nd picture. All works well.

The return line is the PVC with the 90 degree elbow at the top. The underside of this 90 degree elbow is where the noise is coming from as well as my question. There is a little 3/8" or so sized hole under that 90 which is gurgling and causing noise. If I cover that hole with my finger, 80% of the noise goes away. I assume that is a 2nd backup to break siphon, but am not sure.

Do I really need that siphon break on that pipe since I also have one on the overflow? I assume if my return pump stops, the water level will drop to the level of the larger hold on the side of the overflow line....is that correct?

Thanks for any input...

Make this a Herbie.
Main drain pipe cut half way down, emergency just below the wier. Return over the back. I cut my wier hole where the pipe comes thru so my return goes in the corner and out where that is.
Herbie is quiet and you won't have any accidents with overflowing water.

 

[Freenow54]

Thanks Sean,

I am going to try your suggestions and see what happens. Hopefully I can remove that 90 fitting from the standpoint. I hope the previous owner didn't glue it...then I can try a few different holes and see what works the best. Like you said, that hole is above the water line which is causing the noise...If I could adjust the overflow standpipe up 1/4" that would also fix the issue...I think...

If it is like mine you defiantly can adjust it up. It is a " slip " joint