Anti Siphon Hole is making my overflow too loud!

Hi everyone,

My subject line pretty much sums up my issue. My overflow is quite loud, and I have isolated the problem as being caused by the water coming out of the anti siphon hole on my return pipe.

If I cover it up with my finger for a few moments, my overflow becomes quite silent.

A picture is worth a thousand words, so I am attaching one with an arrow pointing out where the hole on the elbow is. The spray from the hole meets water rushing in from the tank, and creates noise.

Can anyone suggest some way to silence this? Obviously I am new to reef keeping, but I do understand the importance of having the hole. I'm just hoping that there might be some way to move or modify the hole to make things quieter.

Any advice would be most appreciated. I will be on vacation soon, so please forgive me if I don't check back in on this topic for a while.

Cheers!

 

I kind of liked the sound it made up to a couple of yrs ago, it makes a "hissing" noise. Thats a "special" 90* elbow that has a pressure hole, all you have to do is replace it with a regular 90* elbow.


luna

 

Usually that hole is just under the surface of the water and so no problem, but I see with your set up, that isn't possible. I'm not too sure what to do, but you can try a check valve in the return line and plug that hole, that will keep the return from siphoning in a power outage and then you can plug the hole and silence the noise.

Best of luck.
Jake

 

Coylee pretty much nailed it. The anti-siphon hole needs to be just below the waters surface, not above it exposed to the air. If it's in the air like you have it, it causes a venturi affect and will make the rushing/gurgling noise. You probably (if not already) will be getting major bubble issues from the return as well with the hole above the water line like that too. Just replace that elbow and drill a new hole just below where the water line would normally be.

 

Change the type return line!!!!! 90 is not working......expiriment?????

 

I think you may need to add another 90 to the one currently there to make an upside down U, then you can add the nozzle to this. This is the only way I can see to get the siphon hole under the water level of the DT. If you put the hole below the surface of the overflow it will siphon out of the DT until the level inside the overflow drops, and depending on the design of the overflow that may not happen.

 

It was someone from my LFS that drilled the hole, not me. I just installed what they gave me. On the assembly instructions, it actually showed the hole on the opposite side of the return, a bit lower on the pipe.

So, I can patch the existing hole, and just drill another just under the surface of the water without encountering any issues? I take it that in the event of a power failure there would be a small amount of siphoning until the water dropped below the level of the hole?

If I can get this fixed, my overflow will be virtually silent and I will be able to hear movies properly on my home theatre system again! ;-)

Thanks for the help!

 

Here's the design of my overflow. Sorry, I should have included a pic of that the first time as well. I think that I'd be safe based on the way that it is designed, but I would appreciate other opinions as well.

Cheers.

 

Okay, now that I see the overflow, you should be good just plugging it and drilling a new one lower. Just make sure you unplug the return pump and check to make sure that it stops siphoning before any overflow occurs. Better to know for sure then find out the hard way.

 

As long as your return is close to the surface and you have sufficient room in your sump a drilled hole is not needed or wanted. I have never had any drilled holes or check valves and I am not concerned about flooding since my returns are only 3/4" below the surface and i always keep sufficient room in my sump for a power outage. in my case with a 100G thats only 3.8 gallons of freeboard or extra room I need to maintain which is a breeze in my 30G sump.