My overflow drain has gas

[outtafocus]

I have found the water in my overflow constantly rises and falls. It goes up an inch higher than I want it, then drops and causes that horrible sucking sound. I am using the hoffer gurgle buster style plumbing.
The water then falls straight down into my sump, but as the above described "flushing" happens the water surges and burps out a large amount of air into the sump, causing splashing and sloshing.

I have read that because my plumbing drops straight down, it causes back pressure in the pipe. Which in turn causes the rising and falling and the burping.
What is the best solution to this issue? I was looking at changing the staight 1"pvc to the flexable style and running it at an angle into the sump. Will this even help?
What are your thoughts and ideas?
Thanks

[vanreefer]

I had the same problem.... I still used 1" PVC but put a 30 degree elbow in it... solved the problem once I made the Gurggle buster as well

HTH

Dan

[Delphinus]

I've had similar issues when I had my overflow go straight down. Not sure if it's a complete solution but having a bend or something along the lines of a 45 so that the water can "slide" into the sump seems to lend itself better to a steady-state operation. There could also be maybe not enough air coming into the overflow. Anyhow just some random thoughts I hope might be helpful, good luck.

[outtafocus]

I will try adding a 45 elbow right below my tank, as it passes into the stand. I will let you know if it worked.
Its kinda funny, my original plan had the 45 in my drain, but after several suggestions, I went with the straight down idea.

[Johnny Reefer]

I'm planning on getting my tank drilled for a side overflow in Oct. or Nov.
Looking forward to hearing about your results! :smile:

Cheers,

[outtafocus]

Adding the 45 helped reduce some of the sloshing and burping, but because it is also adding more back pressure, I feel I am getting more fluctuation in the water in my overflow chamber. Bigger water rise, more pronounced flushing.

I have come to a conclusion that I may have been trying to force too much water through my overflow. When I added the new Rio 20HF pump is when I started to noticed the flushing. I used my ball valve to throttle down my pump and it seems to have reduced but not elliminated the flushing effect. My overflow plumbing has no problem handling the amount of water I am putting through it, but with more water comes more air being sucked in to the system.
I was looking to get away with no powerheads in the tank and relying on the return pump through a SCWD for my only circulation. I think I am going to return the pump and use powerheads for movement.
Now I just need to decide if the Mag7 I own will be sufficient. When I was doing my initial water tests with the Mag7,I had no flushing issues or sloshing. I believe even a Mag9.5 may be to much flow.
Big Als said I could return the pump if I didnt like it.

[BT05]

I only get this problem whenever there is not enough air entering my standpipe or there is a dramatic change in air pressure inside my canopy. Usually when I whip the door open is causes a flush, then settles down shortly after. Doesn't happen if I open the door properly though.

I have a so called "stockman standpipe" which is just the "hofer" with the coupling reversed. So try your standpipe out in the stockman form, it's more sensitive but the amount of air drawn in can be controlled easily. With the Hofer, air is drawn from the drainage holes in addition to the hole in the end cap. Unless the holes are aligned properly, one will always be drawing too much/too little air causing the flushing effect. The stockman doesn't have this problem since the holes are always submerged and enclosed by the coupling.

Then again, this might not apply as my drainage plumbing doesn't drop straight down into my sump but it's worth a shot.

[outtafocus]

By replacing the Rio pump with the less GPH mag7, I feel I have reduced the burping to the point of it being undetectable and the piping entering the sump is at a 45 degree angle. I have also inverted the intake bell on my hoffer gurgle buster and I now have a Stockhoffer gurgle buster standpipe. This have removed all signs of sucking air noise and slurpping.
However the water inside my overflow tower still continues to rise and fall 1 inch. I know this sounds insignificant but it could potentially cause an issue for my auto top off system (Tunze Osmolator) as this rise and fall is felt by my sump.
I have been running a test for the past hour to see what effect this fluctuation has on the Osmolator. So far it seems to be unaffected. I am worried that as soon as I leave it alone for even the shortest amount of time it will want to malfunction.

What is you opinion on this matter?
What do you feel I can do to further reduce the rise and falling?
(the 45 on the drain plumbing is as close to the tank as I could get it, as follows- bulkhead-3" of straight pvc-union-45-8"angled pvc into sump)

[outtafocus]

low water level
http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0906Image0016.jpg
high water level
http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0906Image0015.jpg

[Delphinus]

Basically it's still burping then. You should be able to adjust it, one way or the other, into a steady state. I mean, I don't even see the levels in my overflow chambers varying by 1mm, they're that steady. (I don't have any overflows that go straight down though, all of them have a bend of some sort along the way).

In your case I'm wondering if there is some kind of air flow issue within the overflow pipe. How much air can get in there now? You may need to increase the air intake's ability (drill more holes, or enlarge the hole that's there).

[Richer]

Have you tried increasing the amount of air that gets into your standpipe? (ie. increase the size of the air hole). I found that when I was pushing lots of flow through a standpipe I'd also get the flushing effect you see in youre pictures... after I increased the amount of air that went through the pipe, the flushing stopped altogether, and the level in my overflow rarely ever moves up or down.

*edit*
Looks like Tony get there before I did :lol:

-Rich

[outtafocus]

I have a long length of the air line tubing which came with my mj1200 (the cool black stuff). The air line drops inside the standpipe to about an inch or two below the water inlet holes.
I tried to run it with no tubing and it was horribly loud, constant air sucking sound. Then I tried just a 1" piece of tubing, and it was quieter but the water level jumped like a pogo stick.
I guess I could drill out the hole and glue in a long piece of rigid pipe, but that could be loud to.

[Richer]

What I did was used my smallest drill bit and drilled a hole on top of the standpipe and slowly increased the hole size until the water level in my overflow was constant.
There are quite a few ways of getting air into the standpipe... some more fancier than others.

-Rich

[outtafocus]

I will have to go pick up a new pvc end cap and try out your method. When you finally found the right size, how was the noise?

In taking my stand pipe in and out of my overflow I managed to knock off one of my eggcrate anti-snail fences. Well I guess all experimenting must stop till the silicone cures fully.

[Richer]

There was little noise after I found the right noise. You'll know once you get the sweet spot.

-Rich

[BT05]

I don't use airline tubing either and it sounds kind of like a faint whistle.

I'm not sure about this, but from the pictures, it looks like your standpipe is half the height of your overflow box? I'm not sure this has the height to draw enough air being that far down, but it should really be about the height of the overflow. Also, the standpipe should be a bit larger than the bulkhead (0.5" at least) if you wanted it to handle more flow.

Another thing you might want to try is put some eggcrate and plastic mesh at the end of the drainage line in your sump. This should break up the size of bubbles and help redirect the water away from the pipe. I've found that this stopped the burping in my plumbing and the bubbles created are diffused by prefilter foam. This makes a faint "fizz" sound but I can't hear it when the stand is closed up.

[outtafocus]

Originally the stand pipe was as tall as the overflow. I was testing to see if the height of the stand pipe had any thing to do with the burping. It seems this was not the case. I am picking up the new cap tonight and I will also pick up another stick of 1" pvc, I want to redo my return plumbing aswell.

As for the size of the stand pipe vs the bulkhead, it will have to remain as is. That slip to thread adapter is stuck in the bulkhead. When I picked it up, I was testing thread fit by hand and did not tighten at all, but when I went to remove it, it would not come undone and I didnt want to scar my bulkhead so I left it in. Now with it in the overflow I dont have the room to get it out. I am not worried about it.

[outtafocus]

I just added the full height stand pipe and began the process of trying to find the sweet spot with cap hole size.
All to no avail.
The system that seems to work best is the complete removal of the standpipe. I have just the adapter in my bulkhead at the bottom of the chamber. This causes no rise and fall, no sucking sounds and has great flow. The only downside is the distance the water must fall, this causes the loud waterfall sound, which I cant deal with being only 5feet from my TV.
I have one more plan I need to try before I give up completely. I will cut my drain directly below the bulkhead, leaving enough pipe to glue a 30degree or similar (I hope western pump sells) elbow. If I just use a 45degree elbow from that point the drain line will be in a very awkward position.
Cross fingers.

[Delphinus]

Strange .... I don't think it should be this difficult, I wonder what I might be overlooking here.

Just a suggestion -- on my 20g tank, I have an overflow in the corner, same style as yours (i.e., two glass panes in the corner). It's just a small tank so I didn't bother with a durso or stockman or whatever, I just have a standpipe with a strainer (strainer not really needed, just to keep the {now defunct anyhow} wrasses from going down the overflow pipe since they liked jumping into the overflow). The water level differential is only about 2" at most (I'd have to measure to give you an exact figure, but basically, it's a small drop). Since there's no waterfall effect, it's pretty silent, silent enough for me anyhow.

Anyhow, whatever the outcome, there is a way to make it quiet, keep at it, you'll find the groove that works best with a little trial and error..

[BT05]

It's too bad that the adapter won't come undone from the bulkhead, maybe use more plumbing tape next time? I know that Western Pump doesn't sell 30 or 20 degree elbows since I was just in there last week looking for some 3/4" ones. You might want to try out spa flex with two couplers to get whatever angle you need or use it for your whole drain line. There must be some wierd quirk about your setup making this difficult... I hope it works out, overflow noise can be frustrating.

[outtafocus]

I really appreciate the help everyone has given me.
Thanks for the tip on the stand pipe idea,Tony, it will work so if nothing else I can do that. (I am about to try it out anyway)

Since I am new to the overflow/sump idea I knew I would make some mistakes, but this has been really frustrating. I feel bad because I was taking it out on my girlfriend. I was in the middle of trying different hole combinations and she called and I wasnt exactly the most talkative guy. OOPS.

I figured this was the one thing in reef aquariums where the science was exact, or at least everyone agreed. Water flows over glass, water enters standpipe, water falls to sump, easy right? Wrong.

Thanks

[danny zubot]

How new is this setup and when do you notice the fluctuations? The reason I ask is because when I first set up my 65 gallon I had water level issues when I fed the fish Mysis. (remember that one Tony?) It has since resolved itself, but with some brain storming we came to the conclusion that the fat from the food lubricated my return pump. Thus supercharging it and raising the water level in the tank to the point that the overflow could barely keep up.

If this theory has nothing to do with your issue than I appologize, I didn't quite read the whole thread.

[outtafocus]

The system is basically completely new. -used tank, used pump, new sump.
I am not having issues with the overflow keeping up, its almost the opposite, the air flow cant keep up.

I have however found what I believe to be an acceptable solution.

I dropped in a plain ol' standpipe like Tony suggested. I trimmed it to about 2" below the glass overflow. As predicted it caused no rise or fall cycles. It was a little louder than I would have perferred but it wasnt to bad. Based on this open stand pipe I added an old strainer from a real old Marineland Penguin filter. This caused nasty sucking sounds. Next experiment involved me drilling out the original pvc cap to accept a 7" length of 1/2" ID vinyl tubing and placed it on the Hoffer standpipe, this was really quiet but had a big problem with reduced flow because of the tubing shoved down the standpipes throat. Hmmmm what next?
Stuck the plain ol' standpipe back in, and just for the fun of it I placed the bell from the stockman/hoffer set up (inverted) over the standpipe water inlet so its opening was flush the the standpipe. This amazingly enough caused the open ended stand pipe to be silent. Dont ask me why. But in watching the water enter the overflow chamber I noticed air bubbles going up inside the inverted stockman/hoffer bell, which worried me because the standpipe is only in the adapter enough to hold it in place and could be dislogded if enough air was trapped inside the bell.
I put the bell on the old drilled stockman standpipe and adjusted it so as the block most of the drilled openings. There you have it, I solved the air bubble issue, solved my rise and fall issue and solved my noise issues.
The only problem I could see is a stupid snail blocking off the open end of the standpipe and cutting off all flow, equaling overflowing tank.
I hope vague descriptions didnt confuse any one.

http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0908Image0001.jpg

[outtafocus]

Update: I wasnt happy with my pervious contraption so I set out to build a Durso. This proved to be a fun task seeing as my overflow box is only 4"x4", a standard T and street90ell would not fit.
I basically had to cut the 90 almost in half and remove the enitre middle spout from the T, so it looked like a coupler with a flatened hole in the middle. I then sanded both cuts as square as I could make them. They were ready to go so I used my PVC cement to bond the pieces together. I figured this was where my plan would fail because there was nothing to support the 90 on the T. Well the cement held the 2 pieces together and it is an amazingly strong joint.

This Durso is far superior to my modified stockman. No rise/fall, good flow and even quieter than I had it before. I knew going in that I may have problems with using 1" pvc with a 1" bulkhead (Durso recomends 1 1/4" pvc reduced to the 1" bulkhead) but all seems to be running good.

[Salinity Now]

Can you post a photo? I'm interested how this worked out.

[outtafocus]

http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0911Image0001.jpg

http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0911Image0002.jpg

http://i20.photobucket.com/albums/b213/outtafocuscalgary/2005_0911Image0004.jpg

[Salinity Now]

That's a sweeeeet connection. Now that's thinking outside the overflow box. :lol: