AGA Megaflow Noise

[MSU Fan]

I just recently got a 75g with a built in overflow. I just started up the tank tonight. the overflow is falling into a 20g with a mag 7 return pump.

The problem is that the every 10-15 seconds or so there is a big gurgle of air that goes down my intake pipe into the sump. This is a stock overflow, so no mods done yet.

Any ideas on what is causing this, and is there any way to stop it from making that amazingly annoying sound??? TIA

 

[Cultivatedcoral]

Yeah, I had the same problem with my 75 aga w/megaflow sump. I ran a smaller return (mag 5 I think).

Also, I drilled a bigger hole in the top of the standpipipe and inserted some rigid tubing that comes out the top about 3-4". You can push the tubing in lower in the standpipe and see what works for you.

Eventually the it stops gurgling. Hope that helps.

 

[pjf]

The periodic gurgling can also be caused by the three half-inch-diameter holes on the standpipe just below the water line. Buy some rubber stoppers and place them in the holes to see if this stops the gurgling. The hole opposite the siphon opening is usually a quarter of an inch higher than the other two and should be plugged first.

The water level in the overflow may rise if you plug the holes so be sure to watch the water level.

 

[MSU Fan]

Thanks for the reply's. I will have to look at the stand pipe and figure out what is happening. I have some work to do tonight for sure!

Is there any other advise/options that anyone can think of?

 

[sirjohn]

Check your overflow line into your sump. The line should be an inch or two below the surface of the water level in your sump. If it's down too deep or not deep enough, it will cause the "flushing toilet" effect you are describing.

You'll have to fine-tune it and the AGA "durso" pipe some to get it quiet.

Edit: Oops, meant to say overflow line, not return line.

 

[MSU Fan]

mine is down to the bottom of the sump (maybe 6" below the water line). Should I raise it up a bit first, or after I look at the other suggestions??

 

[sirjohn]

<a href=showthread.php?s=&postid=9985886#post9985886 target=_blank>Originally posted</a> by MSU Fan
mine is down to the bottom of the sump (maybe 6" below the water line). Should I raise it up a bit first, or after I look at the other suggestions??

Well, since raising the overflow line doesn't involve messing with the AGA "durso" pipe (permanently, according to one suggestion), I'd raise it a bit and see what happens. Just hold it up in place an inch or two below the surface and see if the noise goes away.

It all has to do with the pressure of the water rushing down the line encountering the pressure of the water at a certain depth in the sump... and that's the limit of my explanation!

 

[MSU Fan]

well, raising the overflow line didn't seem to work the magic that I had hoped it would. I can't seem to locate the holes that are below the waterline, so I am not sure if that will help (and I don't have any rubber stoppers anyway at this point). I don't want to drill this yet, but it seems like I will have to. ugh.

 

[pjf]

Make sure that you do not have salt clogging the air intake atop the standpipe. Take microwave-warmed RO/DI water and pour it down the air intake.

 

[MSU Fan]

I spoke to the guy that I got the tank from. I think that I have the answer. The plumbing was "hard" plumbed into the bulkhead, which I seem to have bumped, and broke the glue seal. Air is able to get into the system there. I have to order some weld-on and re-glue it. What a pain.

 

[db_triggerfish]

i don't have a megaflow but will soon and i can't stand that "flushing toilet" effect so several months ago when people posted this same problem i learn two things. One: add a cheap airline valve on the very top with a short airline then open or close to regulate the air flow and second: use a lower flow pump or put a T and split the return flow into a chiller, phosban rector, or UV etc. That has seem to have worked for several people.

here is a picture of a fix one person did. sorry i can't remember who.

 

[skey44]

i just had to do a lot of tweaking with a ball valve to match the overflow rate and the return pump... i am running a relatively slow return pump, so i had to dial down the overflow quite a bit. this "dialing in" stopped the gurgling in my case.