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More FAQs about "Durso" & Other Standpipes

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Hi Bob

I'm setting up a new system and i've read that i need to use a durso overflow pipe in my weir?

What exactly is this and how can i buy/build one?  I'm going to have a tank about 3 feet across, and two foot high and about 18 inches front to back.  I want to have the system as quiet as possible please

James, by email

Hello James, the use of (Richard) Durso's model standpipes is quite common in our interest, providing even flows, avoidance of problems of siphoning and some relief from bothersome water mixing with air noise.  These handy drain lines can be easily fashioned of readily available PVC pipe and fittings as illustrated here. Pay attention to the height of the 'Tee' relative to the presumed water level in your system/overflow box. I strongly encourage you to do a bit of reading re these units. Richard's website: www.dursostandpipes.com being a good start, and to read further re a modification, adding an aspirating small pipe line into the long pipe itself'¦ that will allow more air to 'fall' into the line, reducing noise further.

I would be remiss not to mention the need to be very careful re sizing (diametre) of these standpipes. MANY manufacturers and independent tank makers greatly undersize them, making the through-put/hull cut-out too small to allow the desired flow-rate. When/where in doubt, oversize these drilled out holes. Practically speaking they can't be too large; but are way too often too small.

Lastly, I want to state that the last decade or so has seen a trend to recirculating much/most of a system's water in the tank itself'¦ Only running through sumps, refugiums only as much water as need be. I strongly agree w/ this practice; using internal pumps, wavemakers'¦ in the tank. This approach will get you the most water movement at the lowest cost, and reduce noise to a minimum.

Plumbing issue       6/15/15
Hey guys question for you... I just got the new 90 up and running yesterday but today I have a problem... I have a 90 gallon deep blue RR system
<Not the one inch plumbed MarineLand system I hope/trust>
all hard plumbed, reverse duroso in the sump and the stock duroso in the overflow, I am running a Mag 9.5 with a manifold running my uv, carbon and gfo reactors plus the return. I installed 2 RW-8 pumps this is my problem I think. They are placed on opposite ends of the tank, the one near the overflow is pointed downward and the other is pointed straight across the
tank back at the overflow, I have them running in "C" which is alternating pumps. My problem is as they are alternating, the level in the overflow drops and rises and so does my pump chamber which is causing my vent on my reverse duroso to shoot out water. How can I fix this and have you ever heard of this before?
<Yes; I'd try moving the internal pumps first.... to another corner, perhaps just a bit lower in the tank... away from the overflow. I would put a piece of pipe (riser) on the Dursos, and maybe a reducer to like 3/4 or 1/2" w/ a small piece of pipe (just pushed in, no need to solvent) in this/these in turn... to quiet down, reduce splash and spray...>
...I have already drilled bigger vent holes for 1/2 flexible pipe and it did make it silent but no help on the surging water levels...
<And a note again re the diameter of overflows... yours may well need to be larger, re-drilled, or at least added to here... the 9.5 will overwhelm 2 and more 1" IDs. Bob Fenner>

Overflow design    7/5/13
I have 3 questions about overflows;
I want to add an overflow to my 220 gallon acrylic tank.
I want to use a Bean_Animal type overflow to keep it quiet.
<Am familiar>

Bean_Animal Overflow (Reef Central);
This design has a valve on the hose between the overflow box and the sump.
<Yes; of no use really...>
This flow is adjusted so that the water level in the overflow box is high enough that the line to the sump does not take in any air.
<... sigh>
 This results in very low noise.
<There are better (by far) ways... aspirating the line alone is the route I'd go>
 A emergency overflow is provided for when the regular line gets clogged.
<You hope>
I have been having a lot of trouble with this.
The current results of my design efforts; I can't use an internal overflow because the 5" Eurobracing rim around the top of the tank will block access to the box for cleaning.
I can't use a hang on overflow, again,  because of the bracing.
I think I need to cut a overflow slot
<Mmm, not a slot... a circular opening through the back; two.>
 in the back wall of the tank and glue a overflow box to the outside back wall of the aquarium behind the slot.
<Can be done>
I would use 1/2" material for the box and 1" material for the box bottom to reinforce the tank wall.
<Wow; thick material... how would you attach this to the main/display tank?
Silastic for glass; Weld-On for acrylic>
Question1;  Is this my best option?  Do you have any other ideas?
<Is a good option; and many ideas... Most all gone over and over on WWM>
The next question I have is about overflow box size calculations.
There are several overflow calculators online.
The calculators provide a minimum linear overflow length for a specified GPH.
<Yes and yes>
I have the following questions;
a) Are the calculations done assuming a standard 50%  open slotted input screen or without a screen?
<You'd have to check w/ the folks making these calculations; based on what premises. You've seen/read Scott Vallembois' articles on WWM?>
 Some certainly look like a screen is included.
<Yes; and as long as these are not occluded to any extent, not significant in terms of added induced drag/diminished flow rate>
   I plan to use a Gutterguard screen which would be more like having no screen.
<Unless and until....>
   It seems that a 50% screen would require twice as long a overflow as no screen.
<Ah, no... simple enough for you to test, experiment... Do this>
b) What water level difference (head) at the overflow is assumed?
<... per the experimenter/guesser's presumptions or actual testing>
  I need this to determine how much extra volume I need to allow in the sump for when the pump is off.
Oh my friend... DO oversize the sump, AND test for this eventuality, ADJUST and MARK the maximum water level height to allow in the sump...>
   I also need this info to determine how low to put the bottom of the slot on the back of the tank.
<...? Reads like you'd benefit from having someone w/ actual tank, sump manufacturing experience look over your shoulder, at least offer some direct input. Do write Melev's Reef re... say hello to Marc for me... Oh, and MikeK and ScottV at Mom's Aquarium Supply/Glass-Holes.com re the same>
Question2: Can you recommend a calculator that works well and for which the answers to the above are known?
<I cannot. All the ones I've come across have serious flaws; mostly a lack of detail as to their assumptions; not enough discussion re drag, turns, alternatives>

My plan currently is to have 1000 gph with a 22" long overflow using a Gutterguard screen with 2.5" from the bottom of the overflow slot to the top of the aquarium.  I want to run the overflow with a 1" max head at the overflow.
Question3; Will the above plan work?
<Can be made to; again; I wouldn't use, nor count on a valve, raising water level in an overflow... I might use two "Durso" types, one set a bit higher/lower than the other>
How does one deal with these problems?
<Aye yi yi! You do ask good questions... Some folks take to drinking ethanol, others turn their systems into guinea pig runways... I encourage you to read a bit more, settle on a more complete plan; get some help (maybe from a local club member, or a friendly LFS, service company...)>
Do I need to build experimental setups and take measurements?
<Ahh! Perhaps>
Thanks much for you time and help!       Jim
<Glad to be your sounding board. Take care. Bob Fenner>

Durso Stand-Pipe Problem (Maybe Not) – 08/23/12
Hello Wet Web Media,
<<Greetings Felipe>>
I have learned so many things on the site but sadly my problem is so bizarre I don't know where to start!
Ok so let me fill you guys in on my tank; it is a 125gallon with a 15 gallon sump, it has two internal overflow boxes one in each corner, each overflow has 2 holes one is for the Durso pipe and the other is for the return. The Durso pipe hole is 1.5 inches; the return hole is 1 inch (I capped these off because I don't have a strong enough pump).
<<Hmm…perhaps a clue here>>
The Durso pipes are constructed with 1 1/4 PVC pipe, they are correctly made and set up correctly with the water level halfway up the downspout. The sump is not placed in the middle of the tank so the Durso pipe on the left hand side has more plumbing to go to the sump opposed to the one in the right hand side. I'm going to try to help you guys visualize this as much as possible. All the plumbing to the sump is constructed out of 1 inch PVC so the bulkhead that connects to the Durso pipe has a 1inch male adapter on the bottom which results in the 1 inch plumbing. The Durso pipe on the left hand side has the water run straight down for about 5 inches then it hits an elbow, the water flows in 24 inches of PVC horizontally then it hits a 45 degree elbow then maybe 3 inches of PVC pipe before entering the sump. The Durso pipe on the right hand side has the water run straight down for about 5 inches then it hits a elbow, the water flows in 13inches of pvc horizontally then it hits the 45 degree elbow then about 3 inches of pvc (note none of the return pipes are submerged in the water, the water free falls out of them). Now here is my problem, the Durso pipe on the left hand side is the only one that actually has water going through it, by this I mean the water coming out of that pipe is significant compared to the other one where all I get is a very small stream of water. Do you have any idea what could this be?
<<Other than a 24” horizontal run versus a 13” horizontal run there doesn’t appear to be much difference in the plumbing of the two returns…I don’t think this is the issue>>
I have tried everything; I have removed the cap, given it some time, sucked on the top of the Durso, all to no avail. I am completely lost on what it could be. Could you guys please help a rookie out! If this helps I have a Rio 650gph as the return.
<<Barring an obstruction in the slower line (snail/excess solvent glue buildup/etc.), several possibilities come to mind… You can figure that each 1” drain (the smallest diameter of the plumbing in the drain line determines its capacity) is capable of safely gravity-flowing about 300gph. Even with only a couple feet of head loss, it’s very likely this pump just doesn’t have the “oomph” to move enough water to run both drains at capacity…which is not a bad thing (redundancy is good). Another possibility is the tank is not sitting perfectly level, giving the left-hand drain an edge in flow. Something else to consider is the direction of the flow in the tank. If all or even most of the flow/water movement in the tank is toward the left-hand drain, this will force more water down that drain while even pulling water away from the right-hand drain (I observe this every day with my own system when my circulation pumps reverse the direction of my Gyre-type flow pattern). I think one, or a combination, of these issues are the most likely cause for your drain flow issue. If not, then I’d look to inspecting/replacing the plumbing from the right-hand drain line. Hope this helps… Eric Russell>>

Silent Durso 3/13/12
<Hello Douglas>
Just an idea that worked great! Durso was making some typical noise so I just attached a cheap plastic airline valve to a two inch piece of airline tubing, inserted it into the air hole at the top, used the adjusting knob to fine tune air flow and now it is completely silent.
<Thank you for sharing.  Will post for others on our daily FAQs.  James (Salty Dog)>

noisy Durso pipe     2/23/12
I have a 58 gallon reef ready oceanic tank with a 1 inch bulkhead.
<Dang not-so reef ready plumbing! I'd go w/ something larger in diameter for sure... 1.5", even 2">

I built a Durso pipe based on the designs found on your web site � thanks.
I used 1 ¼ pvc pipe.  The return pump is an Aqueon 3000 (630 gph output; 360 gph at 4 feet of head).
<Can't be accommodated by the 1" bulkhead>

It is really pumping the water through and I can hear relatively loud muffled gurgling sounds from the Durso.
I drilled two holes in the pvc cap, but noticed when I removed the cap, the water line did not move and the sound did not change all that much.
<A one inch diameter... can't be sufficiently aspirated to allow this flow rate... Let's see how many more ways I can state this>
Also the water line with or without the cap on is just above the downspout in the Durso pipe (downspout is submerged).
<... again... too much water for this through-put>
I read it should be about halfway up the downspout of the Durso pipe.
<Something like this>
Is my pump too strong? 
<Mmm, yes; one way of looking at this... OR the one inch line is too small, or both>
Should I put a tee on the return pump to dial it back some?
<You could...>
  Will this reduce the noise?
Should I install an air tube in the hole?
<Let me cut to the chase as they say: I'd re-drill the overflow to a larger diameter IF you intend to use the flow your pump can provide... OR cut the flow back to what this line can provide quietly AND add internal circulation...>
This is for a FOWLR tank.
<Doesn't matter>
Thanks for your advice.
<Please read ScottV's piece here re: http://www.wetwebmedia.com/SystemPIX/PlumbingPix/Oneinchart.htm
and the linked files above... Till you understand your choices here. Bob Fenner>
 Re: noisy Durso pipe
OK, let make sure I got this.
The tank has a built in internal corner overflow box with slotted teeth at the top. (the overflow box goes all the way to the bottom of the tank)
The hole on the bottom of the overflow section is 1 inch wide.
<... Too small>
I am using 1 1/4 inch pvc pipe for the Durso pipe and also below for the drain to the sump.
With the current flow through the tank and my 1 inch drain, this is a quiet as its going to get.
Options are enlarge the 1 inch hole or cut back the return flow and add internal circulation.
I currently have an internal powerhead pump but could add another.
I plan on installing a refugium and have read slower flows are better.
<This is so>
After reading your suggested article, I think I will install a Tee in the return pump line to channel some flow back into the sump.
<And you for sharing. BobF>

Overflow questions...   8/16/11
Greetings Exalted Beings of Infinite Wisdom and Light...
<Now this is more like it!>
Long time reader first time asker.
<All bow down>
I have already read a LOT on your site as well as others' about Durso Overflows. I just set up my 120 (first tank with overflows) last weekend.
I NOW know of your (somewhat) collective disregard of 1" overflow holes in a tank this big, but hadn't caught that nuance yet by the time I purchased my tank. So I do have 1" overflows and 1" returns and that's what I'm stuck with for now.
So today I made my Durso Overflows (with 1-1/2" thin-wall PVC per the DIY on Durso's site) and they are DEAD SILENT. I am very pleased.
This is my understanding of a couple of things that I want to be sure I do understand correctly, so please correct me if I am wrong:
<Will do so assuredly>
I am getting a lot of fine (bottle of soda or champagne poured semi-sloppily) bubbles into the sump. This is just because of the aspiration from the holes in the cap on top of the "T" and SHOULD be occurring. Correct?
After installing the Dursos, I also did my first fresh top off into the sump. At first, I expected the water level in the DT to rise slowly as there was equalization between the two tanks as greater water pressure in the sump put greater pressure on the pump, causing it to push a bit more water up top.
<Not appreciably, no>
However, the water level in the DT did not rise at all and the sump just filled up. After thinking about it, I realized that the DT's water level will now be dictated by (approximately) the top of the elbows on the Dursos,
<And the run, and...>
assuming no technical difficulties and I have everything "trimmed" properly. I should now focus on topping off the sump to the desired depth(but, of course, keep one eye on the DT as well!) Yes?
<Yes; but with marking the maximum height/fill that can be accommodated should/when the power goes off, the pump fails>
Thanks much for your input and advice!
<I'd attach bag/s at the discharge of the Durso stand pipes... to dissipate the bubbles, extract the majority of solids... Bob Fenner>
Re: Overflow questions...    8/16/11
Thanks Bob.
<Welcome Mr. P>
Bags on the discharges for the overflows... id est, filter socks?
:<Welcome in time. BobF>

Water Flow/Water tower  2/23/11
Hello Crew, fantastic site, thanks for the wealth of information.
<Thank you.>
Here's what I'd like to do if it's at all possible, I want to create a water tower that is filled by draining water into it from the bottom. The tower fills and then overflows.
Here's the scenario: I have a 500 gallon tank (8'x2x4), it sits on a 3 foot stand. Because of a space issue, I'm building a filtration rack that stands 6 feet tall and has four levels. Without using a pump, I'd like to get the water in the water tower to rise to the top and spill over into the top of the filtration rack and of course at that point, flow back down to sump level (ground level) where the return pump is located.
My idea of how I can get the water to fill the water tower is to have the water from the tank flow into the bottom of the water tower (made out of 2 3' foot plastic barrels ). The water tower will have a 2" bulkhead located 6" from the bottom. The two 1 1/4" overflow lines will be tee'd, the out portion of the tee will be 2". The barrel will sit 2 feet off the floor, so it's opening will be appx. 1 foot lower than the bottom of the tank.
(Finally, here's the question) Will the barrel fill to the top (where there is a spout (if you will) that will allow the water to flow directly into the top of the filtration rack.
Or, am I dreaming
<So long as the level in the barrel is lower than the tank the water is draining out if it will be fine. For what it is worth I would definitely go larger for the tank drains if you can. 1.25" lines will give you about 500 gph each at best. Also, route the overflow from the tank to the containers as direct as possible. Many bends and elbows will take away from the line's flow capacity quite quickly.>
Can't wait to read your response, thanks Lee
<Welcome, Scott V.>
Re: Water Flow/Water tower  2/24/11

Thanks very much Scott. Just a follow up question to be clear.
The water tower is 6 feet tall and the bottom (where the water will enter) is 1 foot below the tank, but of course that leaves 5' feet of the tower above the tank. So you feel this will work, the water will rise all the way to the top of the water tower?
<The surface of the tank water needs to be above the surface of the water tower water. If the upper level of the holding tank is higher, it will not fill up to the overflow and you will have a mess! The water will flow where gravity leads it!>
Lee Granger

plumbing questions for 240 g reef tank, & aspirating overflow lines/Dursos   12/7/10
Hello, I've got a 240 g with 70g sump/fuge combo and would like to know what the quietest(very important) external pump you would recommend for the sump filtration. I've got an Iwaki 40 running now but the noise is unbearable (a very loud hum).
<Good pumps, but typically noisy.>
I've got 2 corner overflows with 1.5 in. Dursos , each with 1.5 in. bulkheads and piping (twin drain lines to the sump). I've got 1 in. return lines going back up into the overflows. Also what would the recommended
sump only flow be for such a setup. My LFS claims I should go with a 4000 gph pump just for the sump return!
<Ah, um, no way! These overflows will handle 1800 gph in the best of scenarios. I would look towards an Eheim 1262 to fit the bill here. Near dead silent, lasts forever and will give you 900 gph minus head pressure, plenty of flow through the sump on this system. This will leave you with a quiet pump and quiet overflows and true redundancy.>
He may just be trying to sell me a pump.
<And/or just has no clue.>
I'm getting a constant siphon effect on my Dursos and I'm experimenting with aspirating. Do I just insert a 1/8 " rigid airline tube down through the 1/8 " hole in top of Durso cap?
<Yes, but for lines this size I would drill the hole out a bit larger for a bigger line, 3/16"-1/4" I.D. or so.>
How far down should the end of airline tubing go?
<It will vary, but generally just a few inches. You can just slide it up and down to find the spot that quiets the line, stops all siphoning.>
And should the top of the tubing be several inches above the aquarium?
<Just high enough to always be above the waterline.>
I just couldn't find a definitive answer. Thanks for your help.
<Welcome, Scott V.>

Mag 12 / 100G / 1.5 stand pipe (Durso)   12/6/10
Hello Crew,
Just one quick question, Is Mag 12 too much for a single overflow with 1.5" (Durso) stand pipe on a 100 G reef tank?
<Once all the plumbing is accounted for a 1.5" will technically handle the flow of a Mag 12, but you will be right on the edge of the overflow's capacity, with no redundancy. The slightest little occlusion will lead to your tank overflowing!>
Thanks/ Jun
<Welcome, Scott V. Do take a look here:

Surface Skimming Problem 1/5/10
Happy New Year to you all,
<Thank you from the crew and may you also.>
I say this every time I write, I know, but I love this site, and I appreciate all your knowledge, experience and willingness to share.
<We thank you for this.>
I need a bit of advice. I have a 90 gallon AGA soft coral reef with just a few fish. The internal corner overflow is not skimming the surface of the water. The water rises a bit above the cut out slits. This problem started when I upgraded to an Eheim 1262. I have one 1 3/4 inch Durso standpipe. The water level in the tank does not change when I block the standpipe vent. Do you think I should modify the slits? Perhaps use a Dremel tool to widen every other slit or just cut off a section and cover it with plastic gutter guards? Any advice would be appreciated.
<Victoria, there is no PVC pipe size that is labeled 1 3/4" pipe. A 1 3/4" inside diameter would be close to a 1 1/2" PVC pipe. Which do you have, and what is the size of your bulkhead fitting? I'm thinking your new Eheim (900gph) is putting out slightly more gph than your bulkhead fitting can pass which leads me to believe your bulkhead fitting is 1 1/2". With no other restrictions in the drain line such as elbows, valves, tees, and/or the use of ribbed hose, a 1 1/2" bulkhead can pass approximately 975 gallons per hour. With a few restrictions added, this can drop significantly. I don't believe making the slits wider is going to help you much as long as the square area of all the slits is equal to or greater than the inside area of a 1 1/2" pipe. A good test would be to remove the slitted standpipe if it is not glued to the bulkhead fitting and see if the water level drops inside the overflow.>
Thank you for your time,
<You're welcome. James (Salty Dog)>
Re Surface Skimming Problem 1/5/10
Thanks for the speedy reply.
<You're welcome.>
You stopped me just in the nick of time. I had the Dremel tool in hand, ready to go. Just kidding. I could not remove the entire standpipe as it is a threaded fitting, and bad things have happened in the past when I removed that standpipe.
<Oh yes!>
I did remove the Durso fitting, as it is a slip fitting, and the water inside the overflow section dropped to the top of the standpipe, and the lovely slurping began. The level of the water in the display dropped only a hair, but stayed well above the overflow slits. So does this mean the bulk head is not restricting the flow? What should I do now? I do have my Dremel tool in hand.
<Sounds like you are trigger happy with that Dremel (Ha). Is the small vent hole in the Durso plugged up with calcium/debris? If so, try cleaning up the hole and if that renders no help, try increasing the vent hole size slightly and see if that lowers your water in the overflow.. If none of these suggestions help, do send pics of your Durso and the front of the overflow weir so I can get an idea of what you actually have.>
Thank you for your time,
<You're welcome. James (Salty Dog)

Clogging Durso Stand Pipe 10/29/09
I have a Durso design standpipe that functions reasonably well. However, I'm having a continuing problem with the vent hole in the top of the cap clogging from salt.
<This is rather common.>
As you know, these vent holes are typically quite small - mine is 5/64". Every day or two at the max I have to swizzle a toothpick around in the hole to clean out salt spray. If I don't, the hole  gradually passes less air, the siphoning effect starts with the standpipe and the water level drops. Clean out the hole and the water level comes right back up to where it's supposed to be. I don't know if the clogging is happening because the vent hole is drawing in warm, moist tank air or there's actual splashing going on inside the standpipe. Or maybe a bit of both?
<The problem is likely caused by a bit of both.>
Any suggestions on how to eliminate this salt spray clogging problem?
<You have a few options, the simplest method will likely be to slightly widen the hole using a drill bit. The wider you go the louder it is, but likely you can go to at least 1/8" or even 3/16" without experiencing a
large increase in noise. It also is not uncommon to add some airline tubing to extend the opening up higher, this will decrease splashing from the overflow, however it will not stop clogging from splashing inside the
Durso pipe.>
<Good luck, Josh Solomon.>

Re: Durso vent hole clogging -- 11/03/09
I feel like I'm missing something here. If you didn't have a hole in the standpipe I think you would most certainly have a siphon, at least until the water level fell enough to expose the overflow to air which would break the siphon.
<You are absolutely correct.>
So I don't see how having the hole is bad - in fact I think it's an essential part of the design.
<Yes it is, perhaps I was unclear but I was trying to encourage you to make the hole larger, not to get rid of it.>
If you had the standpipe wide open at the top you might flow x GPM just by plain gravity. If you had a full siphon you might flow 3 or 4 times x. This tiny hole in essence throttles your drain flow somewhere in between plain gravity and a full siphon. Based on Richard Durso's (and others) designs, they all have some sort of hole to allow air to enter and prevent a full siphon.
<You are right in your understanding of the Durso tube, however I was encouraging you two enlarge the hole since the variation in speed of drainage you described is symptomatic of a siphon from too small of a
I have modified my pipe and replaced the cap with a 90 elbow and a threaded plug. I drilled a hole through the side of the 90 and through the plug.
By screwing the plug in or out I can alter the size of the hole - from nothing to the full diameter which I think I made 1/4". So hopefully the 90 puts the plug and its hole further from the salt spray and it won't clog. If
it works, I'll report back and include a photo for reference.
<Excellent design Alan, this is a common fix to the issue.>
<Josh Solomon.>

Re: Clogging Durso Stand Pipe 10/29/09
Thank you for your reply.
I've tried a larger hole and unfortunately it slows down the drain forcing a corresponding reduction in the return volume to keep the water level where it needs to be. The current size seems to be the perfect balance between supply and drain.
<Perhaps I am picturing something incorrectly, but in general if placing a hole in the standpipe lowers the overflow rate, then you have a siphon going all the time, not a good thing if you haven't planned for it.>
Regarding the tubing, can the tubing extend down into the drain water and still serve its purpose? I haven't tried that. Perhaps doing that and having the other end outside of the tank canopy would solve the problem?
<It is a possibility, but don't put it under the water level, or it will cease to serve its purpose.>
My other thought was to put a 90 degree elbow and plug on top of the standpipe instead of the cap. Then put the vent hole in the plug, effectively moving it further away from the salt spray. They're cheap enough to try but do you think I'm wasting my time?
<No, that doesn't sound like a bad idea if I am understanding you correctly, however my large concern is that you said the Durso stand pipe drains slower when you make the hole larger. It really sounds like you
have a siphon going.>
<Good luck, Josh Solomon.>

Re: Clogging Durso Stand Pipe -- 11/04/2009
<Hello again Alan.>
I believe my problem is solved. I've attached a photo (excuse the white balance please) to show what my final solution to this problem is. From left to right in the picture is a 1.25" 90 , a 1.25" to 1.00" threaded
reducer and a 1.00" threaded plug. Note the 1/4" air vent hole drilled through the side of the reducer. Inside of the reducer the threaded plug controls the opening through this hole. Thread it in and the opening is
restricted - out and the opening increases. The purpose of the 90 was to get the hole further away from any salt splash from the top of the standpipe. The only reason for the reducer is I couldn't get a 1.25" threaded plug. If you can, then as long as you use a slip x thread 90, you can eliminate the reducer, drill the air vent in the 90 and accomplish the same thing.
I've been running this for 9 days now and haven't had to clean out the hole once. Before, I was doing it every 1 - 2 days.
<Thank you for sharing, and for the photo.>
<Josh Solomon.>

Durso DIY, missing pix  6/30/09
Hi Bob,
I was going to include a ink on the DIY Durso Standpipe I wrote for a query I answered today. The article is there, but no pics.
<Mmm, will look for graphics on the morrow. B>

Standpipe adjustment -- 6/14/09
<Hello Jason>
I have a Perfecto factory drilled 75 gallon aquarium filled with saltwater and 45 lbs of live rock. I would like to change out my standpipe in the overflow chamber (I think I made it a little short).
Is it safe to do this while the tank is filled with water or do i need to drain the entire tank before messing with the overflow chamber?
<Jason, assuming that there is appropriate empty space in the sump to catch the additional volume of water from your overflow which will quickly drain, then there should not be an issue. Carefully remove your standpipe being careful not to torque or put any unnecessary pressure on the bulkhead it is sitting in. Replace with the longer standpipe and watch the sump go back to its normal level.
Don't stress, take your time, and be easy on the bulkhead. There should be no need to drain the tank if the overflow is properly sealed to the tank.
Josh Solomon.>

DIY Durso Standpipe 3/27/2009
Hello lucky Bob,
<Just as lucky James>
I did an article today regarding above subject. Feel free to use it on our site if you wish.  I searched for this on our site and came up with nothing so thought it may be useful.  Are you water logged yet?
<Not quite... though bastante viento ahora! We gave up after one dive today... Might I suggest you change a couple things here? I'd drill the hole in the top cap a good/stated 1/8" diameter for the purpose stated... And I don't think upsizing/bushing to larger diameter fittings does a thing to quiet water flow noise. BobF>
Have fun,

Re: DIY Durso Standpipe 3/28/09
I agree that upsizing does nothing to quiet the water flow, but do believe it helps maintain a more constant level in the overflow. Agree/disagree?
<Mmm, I do disagree... the diameter of the pipe is the rate limiting factor here. RMF>
<James, I can tell you from actual testing it does none of the above...it is a "wives tale" started by someone years ago in the forums. Scott V.>

Oversized drain and noise 2/21/09 Hey guys, hope you're all doing well! <Hello Dave.> Wondering if you can clear up some confusion for me. <Sure thing.> I am about to pick up a standard dimension 120 gallon tank with a single internal corner overflow with two 2.5 inch holes in the bottom. <Wow! A tank with appropriately sized throughputs out of the box for once.> One is going to be used as a drain, and the other for return. I have a 30 gallon sump, and an Eheim 1260 for a return pump. The expected flow out of the sump, taking head pressure into account, will be about 430 gph. <Reasonable expectation.> I have been reading your website regarding plumbing, and have the impression that I should go with the largest bulkhead and stand pipe I can fit (being 1.5 inch) for both redundancy, incase there's a partial blockage, and to keep the noise to a minimum. <Yes, exactly.> I contacted Richard Durso on his web site to ask about his 1.5" standpipes that he rates at 1500 gph, but he encouraged me to go smaller, because of the relatively low sump flow I have planned! <Whoa, red lights, sirens going off. There is no reason to go smaller...this is like saying you need a smaller garage door because your car fits in too easy. And a 1.5" line will flow nowhere near 1500 gph. 750 gph is a good working number, almost 900 gph in the absolute best case scenario with all of the planets aligned properly at 12 noon on the vernal equinox. I am aware his site claims 1500 here and 600 gph out of a 1" line, but these are both far cries from the real world, actual quantified testing. For those that want to see: http://www.dursostandpipes.com/?page_id=14| To get the skinny on what is really going on read here: http://wetwebmedia.com/SystemPIX/PlumbingPix/Oneinchart.htm  this is only about the 1" bulkhead, but the 1.5" bulkheads are way overrated in the industry in much the same way....sorry to be so long winded about this, but there are so many sources out there misleading people about overflow rates that have so obviously never quantified the actual flow.> He said that such over sizing would actually make things louder because a lot of air would be getting sucked into the pipe due to the minimal water, and produce a boiling water kind of noise!? <Hmm, no. The amount of air drawn into the line has nothing to do with line size, it is all about how much volume the water displaces in the line as it moves through.> I could go with the 1.25" pipe he offers, which is made to fit a 1.5" bulkhead, however this goes against everything else I have read, unless I misunderstood. <You did not misunderstand, going smaller does indeed lower your draining capacity, to the tune of 300 gph or so in this case.> Which is it, does over sizing the drain increase, or decrease the noise? What do you recommend? <Keep it 1.5", if you read through many of the online forums, many if not most out there advocate actually making the standpipe itself larger for noise reasons. There is not any validity to this either IMO.> Also, given my two 2.5" holes, how large of a pipe and bulkhead hole would you use for the return...is there any benefit to over sizing this as well, to a 1.5 incher... or should I stick with the more common 1" or 3/4"? <Stick with 3/4" for the flow you are talking about running.> Thanks very much, Dave <Welcome, Scott V.>

LOA <Lights of America, brand... fuge lighting> install instructions if you want them, Standard Durso Issues <noise, flow...>  2/11/09 Hello, <Hello John!> Well I'm getting there on my 65g as a first timer. I have the sump and fuge running and have some rock on order :) <Great!> ------------------------ On the LOA fuge light: ------------------------ Thought I'd pass on how I hooked it up as it's probably a little different, and more detailed, than what I've seen on your sight. It a very safe implementation, as it keeps the light off of the fuge cover and offers a toggle switch for convenience. You need the following: 1 Plastic Outlet Box w/threaded knock outs 1 Cord strain relief (via compression fitting) liquid tight connector w/male box threads 1 Box cover with plastic switch toggle on it (usually red in color) that has a 'marine' mark stamped on it. 1 15 amp toggle switch w/ground screw 1 Cord w/plug (Has to be 3 wires Black, White, and most importantly Green!). Instructions: Remove box knockouts first, one on the back and one on the side. Attach box, using the back knockout hole, onto the light stem w/silicone. Attach strain relief connector into the side knockout of your choice. Insert cord into the strain relief connector leaving 4-6" of cord in the box and then tighten the nut on the cord forcing a good compression fit. This connector is critical as it prevents cord movement and will also end up being water tight. Install switch by connecting the black wires to the screws on the switch, connect the white wires together via wire nut, connect cord green wire to the green screw on the switch. Install box cover by placing the red switch toggle on the back side of the cover, over the wired switch's toggle. In this case the cover serves as a switch for the switch and keeps your salty wet hands away from the real switch itself. The enemy here is not getting a shock, but rather corrosion within the switch, which eventually means a fire inside of the plastic box. You now have a liquid tight working light with a big red toggle switch on the box for turning it on and off. <Nice.> You can now use the 4 holes on the outlet box to run string, cord, etc.. to hang the light from your stand, so it hangs 1" away from your acrylic fuge cover. Attach your string to an eyelet above so when you work on the fuge you can simply grab the cord from the eyelet and move it away. You can now use the light's stem screw to adjust the angle of light entering the fuge. Finally, silicone over all metal screws once you have it adjusted to extend their life span from corrosion. Plug your light into an outlet w/GFCI protection. I hope this helps someone. <I have no doubt it will, these are great inexpensive refugium lights. Thank you for sharing your instructions.> ------------------------------ On my Durso overflow gurgling: ------------------------------ Sorry to trouble you with this very common problem, but I was not successful in using the aspiration trick. It's the crappy 1" drain thing. Where were you guys when I bought my tank! I blame you all ;c) <Well if the things would just flow as advertised there would be no problems!> Kidding aside - I'm running a puny Mag5 and I inserted air tubing (smaller than the standard 1/4" ID) down the air hole and moved it around to various depths and it seemed to make no difference. Do I really need to back down the flow from a mag5? <Hmmm, you may have to from what you describe about your overflow line below. These longer runs do have an impact on the flow ability of the drain.> Sheez.. I did not go below the bulkhead in terms of depth as I was afraid of the air tubing coiling down at the bottom, resulting in eventual overflow clog/block. Do I need to go below the bulkhead joint? <On a bottom drilled tank with a standpipe? No. The line should end within the first few inches of the standpipe, near the top. This is where you need to introduce the air, break the siphoning.> My return line is far from ideal, it has 2 90's and a horizontal flow, with a decent slope however. This is because my sump is in another room. If I could do a redo, how many times have you heard that one!, I'd drill 1.5" holes in the back... <Well, think of how long you will have this tank, how much more comfortable you would be with larger drains. You don't even have rock in the thing yet, the time is now if you have any inkling to drill larger holes! Not just for more flow, but for redundancy.> Anyhow, as a side note the water line is consistent so it's not siphoning. <Good.> I'm wondering if I should try a larger ID air tubing?, or maybe even rigid air tubing? There is quite a bit of noise coming from the inserted air line, making me wonder if the ID is too small? <It that the noise, the aspiration line? If so check out http://www.wetwebmedia.com/pbnoisef4.htm, the fifth query down or so. It is a simple and cheap silencer that will quiet that line down to a whisper.> Not sure why this isn't working based on the success of other WWM posts? <It sounds like it is working fine if your water level is consistent and stable. If the line noise is the issue, try the silencer, it works wonders.> Thanks as usual for any help. John <Welcome my friend, and thank you again for sharing the Lights of America tips. Scott

Durso Sucking Air 10/29/08 Hello Crew, ?I have just finished setting up my new custom tank and am having some problem quieting my Durso standpipes. This is my third reef setup and I've used Dursos on each. I may not be fully understanding the responses when Googling your faqs so I need to try and explain what I'm experiencing. <Okay, we'll hammer it out.> My set up includes a 200g corner acrylic pentagon with two 1.5" drains and 2 1" returns in the back corner. The tank drains to the basement and there I have two 110g sumps containing rock/chaeto/deep sand bed. My return pump is a Reeflo Barracuda that is rated for about 1600+ gallons at my 16' head height. It gives a very nice flow through the 1" fittings. The sound going over the back overflow is negligible. <Good, do also realize you drains are at the upper limit of what they can handle.> I constructed the 1.5" dursos per instructions (as I've done before) and was able to drill holes in the caps big enough to stop the cavitating water level, but then the air noise going through those holes is much too loud. I believe 3/8" was the largest hole drilled after moving up through the progression of drill bits. <Lots of flow means lots of air which equals lots of noise!> I decided to start over and go with multiple smaller holes to no avail. Still the same loud air sucking sound. Also tried was the varying of heights of the standpipes. One pipe is now about 1" taller. This was a suggestion of my tank manufacturer. To start this process the were exactly the same height and the "T" is about 2" below the overflow teeth. <The pipe height will make no difference, the water level in the box will adjust accordingly.> One other thing tried was to push some 1/4" flex tubing down the holes in the cap anywhere from 1-18" and still no good results. Also, the sucking air noise can be heard if the pump is going full force or ball valved back to almost nothing. <Yes, the air will still be brought into the line.> What might I be missing? <Nothing, you have done all correct, but there is a cure for this problem. See http://wetwebmedia.com/thrhullplumbng.htm, the third or fourth query down, dated 9/19/08. This explains the solution you are looking for.> This isn't a problem I've experienced in the past. Thanks for you time. Jeff <Welcome, Scott V.>

Re: Durso Sucking Air 10/29/08 Thanks for responding Scott, I read the thread and am envisioning a "pipe bomb" looking thing sitting on top of my already drilled cap, connected by tubing with a smaller section of tube coming out of the top of the "pipe bomb". Am I reading this correctly? If I am mistaken, where then does this contraption mount? Regards, Jeff Butterbaugh <Yep, you have it. A much better description than mine! Sounds odd, but works like a charm. Scott V.>

Thanks! Silencing pb overflows  10/8/08 Just wanted to say thanks for your wisdom regarding silencing Durso overflows. After I moved my sump to the basement, the overflow rumble was very noticeable. By adding two ¼" ID airlines into the Durso head, each about 2' below the top of the water, the overflow is now silent except for the waterfall into the box. <Glad you found what you needed!> Much thanks! <Cheers, Mich>

Durso Standpipe Misbehavior. Durso Standpipe Question 1/30/08 Hey Crew, <Hi Andy> I¹m in the fourth month of preparing for my second foray into marine aquaria after a long hiatus; planning to launch my tank (Oceanic 76g Half-Circle) March 1. I¹ve read, read, and read some more (first ³equipment² purchase was CMA...thanks, Bob!), and I¹m feeling like I¹m almost ready to go (funds, of course, being the long pole in THIS tent). Anyway, I plumbed my tank this last weekend in preparation for a wet run (in the garage, where noob mistakes won¹t do much damage); <Good planning here. Wives are easily irritated in this regard.> I¹ve fiddled here, tweaked there, and finally got things down to where I¹m fairly comfortable with the safety and efficiency of the set up. I initially plumbed with flexible tubing, but I wasn¹t comfortable with that at all, so have now hard plumbed it (with the exception of a short piece of flexible tubing between the submersible return pump (Mag 7) and the hard PVC, to damp the vibration a bit). <Does help some.> I won¹t burden you with details on the plumbing, because I¹m not entirely sure that it¹s relevant to my problem (or the solution to it!). My problem is that my Durso standpipe (the one that came with the overflow accessory kit from Oceanic) tends to resonate with the ambient vibration in the system (naturally), and this causes it to occasionally detach from the bulkhead (even after cramming it in there nice and tight!). Now, I¹ve run through all of the possible plumbing/pump failure scenarios, so the extra water from the single, center overflow doesn¹t overflow the (30g) sump (even coincident with a pump/power failure), but nevertheless it¹s annoying. I plan to dry the tank out before installing it in the living room and tweak some of the remaining small issues, and I¹m wondering if there are any obvious solutions to this problem? Can I just put a few dabs of silicone sealant on the drainpipe to secure it a little better to the bulkhead? Any other suggestions? <Hard plumbing will always result in resonance, which is why I prefer using flexible hose. If you are bent on the hard piping, a few dabs of silicone on the standpipe may give you problems if you ever need to remove the standpipe for cleaning etc. I'm thinking if you coat the pipe with a heavy silicone lubricant and then insert, the adhesiveness of the lube may very well keep it sealed in the bulkhead. Also make sure there is no sharp edges around the end of the tube, high spots here may impede the effectiveness of the seal. This lube is generally used on "O" rings and is available from Drs. FosterSmith and is perfectly safe for use in aquariums. The part number is AEL-907904 and is $3.99.> Thanks, <You're welcome. James (Salty Dog)> Andy Re: Durso Standpipe Misbehavior 1/31/08 Thanks, Salty. Seems kind of counter-intuitive, using lube to hold it IN :-), but I¹ll try that. <It's the high viscosity of the lube that should act like a suction. I think it will work, if not, call me a few names. Good idea to have some lube around, is used to coat "O" rings/seals on filters and such. James (Salty Dog)> Andy

Issue With GARF Plenum Standpipe -- 01/23/08 Hey guys, <<Hiya>> I just set up my 120T yesterday, and included (for the first time) a plenum. I constructed it according to the directions on GARF, which included a standpipe that connects to a powerhead, which is to be pulled out after two weeks. <<Mmm, yes'¦have read about this>> My question is, when I put the powerhead on the pipe, 1) it started shooting out a bunch of sand, which actually made the pump stop on three occasions before I put a sponge in the pipe to serve as a filter - is this normal?? <<Wouldn't think so. Although the pump should pull out any nearby fine sand that managed to get in to the plenum space during construction, I wouldn't have though the volume to be enough to clog/stop the pump unless something is amiss>> And 2) now my sand bed is sunken down all the way to the plenum at the base of the standpipe, despite having had a layer of screen on top of 1" of sand, which was on top of the plenum. <<Mmm, not sure I understand you here'¦but there should have been a layer of screen on the plenum/eggcrate (I believe GARF even states to 'wrap' the eggcrate) to prevent sand from entering the plenum 'void' space. If you do have the screen on the eggcrate, then perhaps the substrate you used is too 'fine'>>>> Is this hole, essentially, to the plenum negating the point of the standpipe, namely, to be drawing water down through the whole sand bed since there's now a hole? <<If you did not 'seal' around the pipe with the screen to prevent such'¦yes>> I tend to be a worrier and a perfectionist, so I am not sure if this problem is more a symptom of these personality flaws, or if my plenum is somewhat pointless at this time. <<Does sound to me as if you may have an 'engineering' issue. Perhaps a call to GARF for better clarification is in order. Either way, I think if you want to use this as a true plenum you will likely have to pull everything out and start again. Else'¦let it all fill with sand and use as a DSB >> Thanks! Alex Bracke <<Happy to share. Eric Russell>>

Standpipe Design Question...And A Definite Need For Some Reading/Research...And A Bit Of Patience -- 10/14/07 I have a 55 gallon tank that I want to make "reef ready". The only drill bit that I could find to make the hole in my tank is a 1-1/4" diamond grit drill bit. <<Does not fit common bulkhead sizes'¦you can find a wide selection here (http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/MAIN.htm), or do your own keyword search on 'diamond core drill bits'>> (I'm not big on internet shopping.... well I'm not big on waiting :) ) <<Doesn't change the fact you don't have the right tool to do the job>> I bought the bit and practiced with it, but still haven't drilled my tank. <<That's a good thing>> When I do finally drill it, I should be able to slide a 1" PVC pipe through the hole, after sanding with O.D. down just a hair? Then I want to seal around the hole using aquarium sealant. Do you think this would be safe? <<Absolutely not! What you propose will only lead to grief'¦ You need to drill an appropriately sized hole and install a proper bulkhead fitting. And for this application I recommend a 1.5' bulkhead, which requires a 2 3/8' hole>> I have been having a hell of a time finding a bulkhead to fit this size hole. <<Match the hole to the bulkhead'¦not the other way around>> I am planning on making the Durso type standpipe and was also thinking about making two of them. I'm figuring it's a good idea incase one clogs. <<Mmm, two 1.5' drains are more than you need for this tank in my opinion'¦but you can do this if you want>> If I do use two of them, would I have to drill the air holes in both caps? <<I would>> Would I have to do anything to balance them out as far as them moving the same amount of water? <<Make them the same height>> Would you recommend using one or two stand pipes with the 1" pvc? <<I think one would be fine'¦and the recommended diameter for the 'Durso' standpipe is 1.5''¦even if you use a 1' bulkhead>> I am not sure which return pump I am going to go with. I am leaning towards this pump or this one. <<huh?>> Is there any downfall or upside to using an external water pump? <<Pros and cons to both (external vs. submersible). I prefer the submersibles for most applications as sump return pumps as I find they are generally easier to plumb and produce less noise>> My return line is 3/4" flexible tubing with a J type hanger made 3/4" from pvc. Thanks again for all your great advice. <<Please do read here and among the associated links at the top of the pages (http://www.wetwebmedia.com/plumbingmarart.htm). Regards, EricR>>

Overflow Issues'¦Sluggish Drain Lines -- 09/30/07 I just recently moved and set up my 125 Gal. tank with a 29 Gal. refugium. <<Neat>> About a week after having it all run smoothly, the tank has started overflowing. <<Uh-oh>> I have two Durso Standpipes on opposite corners of the tank using 1" piping. The two overflows were joined at a T-fitting, which led to a ball valve, then a 45 degree coupling at the end, which is about 3-4 inches below the top of the water line of the overflow section of the refugium/sump. <<Mmm, I see'¦having the two drain outlets conjoin at the ' T ' reduces the overall drain capacity of the pair as you have reduced all to a 'single' one-inch drain from that point on>> I have a Pentair Quiet One 3000 (780 GPH) running the return line on 3/4" piping. After it started overflowing the tank yesterday, I re-plumbed the overflow to allow both lines to run independently into the sump at about the same depth in the sump. <<Ah, good>> This didn't seem to have much effect. <<Hmm'¦something else must be amiss. After subsequent head-loss, I would expect the flow rate of your stated pump to be fine for the two 1' drains (figure a maximum of 300gph per drain)>> So, I tried to silicone the vent holes on the top of the end caps, which kept the overflow from draining at all. <<Yes, an escape route for the entrained air is a necessity. You might even try some experimentation with inserting differing lengths of rigid tubing in to these vent holes to see if you can find where the air is trapped/building and thus most efficiently expelled/released, allowing more water down the drain>> So, I gradually enlarged the vent holes. I noticed that one end (the end that is closest to the overflow section of the sump and flows nearly straight downward into it.) has a smaller vent hole, and drains at a much slower rate than the other end. <<Hmm, sounds like maybe the designer of the system was trying to 'balance' the flow rates between the two drains'¦which would only be possible by limiting the flow in one, thus reducing the overall rate even further (less than the 600gph max stated earlier)>> Could I have a snail impeding the flow that severely on that one end? <<Is a possibility, yes>> And if so, how do I convince it to get out? <<It will likely require disassembly of the standpipe or 'poking' it out with some type of flexible instrument (semi-rigid plastic tubing)>> Or is it more likely that my plumbing skills really suck? <<Hard to say without more information on your plumbing configuration. But try removing the standpipes and see how the tank drains'¦if you're lucky, any re-engineering may just be limited to these>> Any suggestions you have are greatly appreciated. <<It may well be that your plumbing design/configuration limits the drain capacity of these outlets more than realized. Once you determine there are no blockages (snails) in the lines, install a gate-valve on the output side of the pump and adjust the to where the drains can handle the flow and see if this is suitable'¦a flow of only a few hundred gallons per hour through the refugium should still be fine>> Thank you, Jules (Portland, Oregon) <<Happy to share. EricR (Columbia, SC)>> <Bigger drain lines... RMF>

Drain Plumbing Suggestion (More To Consider Than 'Maximum' Flow Rates) -- 08/21/07 Hi Crew, <<Hello Tom>> No question this time, just a quiet way to plumb a higher-than-average flow rate to a sump with tanks commonly built with the two bulkheads in the floor of the overflow. <<Cool...let's hear how you did it!>> Usually the large one is used for the drain, and a smaller one for the return. <<Is the manufacturer's intent, yes...sadly they size of the throughputs is lacking/insufficient to be truly practical>> I'm sure this isn't an original idea, but it works well and doesn't require drilling more holes. My tank, about 130G, came with a 1.5" and a 1" bulkhead in the overflow. <<Wow, usually this configuration comes as 1' and ¾' respectively...yours is better than most and a huge improvement re. Is this a custom tank? If this is a 'stock' tank can you tell me the manufacturer?>> I use both for drains: <<Ah yes...this is actually quite common>> The larger drain goes to the sump's skimmer section, and the smaller one goes to the fuge. <<Putting to good use>> The fuge overflows back into the sump return area, and then the return pump line goes up and over the back of the tank to a corner nozzle. <<Very good>> By using a Stockman overflow on the main drain, and submerging the fuge drain several inches below the water line, I get a very quiet 1200GPH throughput <<I think you mean through the two drains combined, yes?>> ...before these mods it sounded like Niagara. The valve on the fuge drain allows for a wide range of flow and it's set so the fuge gets the flow it needs, and the rest goes to the sump. <<Indeed... But if I may suggest... Shut off the valve and make sure the Stockman can handle the full flow through the overflow on its own. Should the drain to the refugium ever become plugged; as with a snail caught at the valve junction, you will need to make sure your flow rate is not such that the remaining drain becomes overwhelmed thus creating a flood. You will likely discover the 1200gph is not 'practical' re>> Sometimes I'll open the fuge drain all the way for a few seconds to give the fuge a little flush-cleaning. I do use a closed loop on another pump for more circulation, but now wish I would have used Tunze Streams or Koralias for lower power and more flexibility. <<I employ the Tunze Stream pumps in my reef display...fabulous devices>> Tom <<Thank you for sharing. EricR>>

Re: Drain Plumbing Suggestion (More To Consider Than 'Maximum' Flow Rates) -- 08/21/07 Hi Eric, <<Hiya Tom!>> Flood potential was most definitely on my mind when I first tested this setup since the tank sits in a carpeted living room. <<Indeed>> The fuge drain does get closed fairly regularly, like when I'm cleaning the display and I want it all draining through the sock. <<I see>> The 1.5" drain handles the full 1200 GPH, but there is more noise from the Stockman at full load since the Stockman air intake isn't tuned for it. <<I'm sure there is, but at least the 'noise' won't ruin the carpet/enrage the significant other. And 'tuning for noise' aside, this is about 400gph-500gph more than I would suggest for a standard 1.5' drain. I'm sure the Stockman standpipe is helping here but...are you certain of/have 'tested' this flow rate to be sure it is accurate? I don't doubt your veracity...just am very interested in this performance>> But it all quiets down when the two drains are used together as described earlier....and a separate pump to feed the fuge isn't needed. <<Sounds like you have it under control>> The tank was from Premium Aquatics, <<Hmm...did 'they' build it?>> as was most of my equipment. PA is great to work with. <<I have dealt with/ordered from PA many times...and would agree>> I do check/clean the Stockman occasionally since a blockage there could be a catastrophe, <<Indeed...and a very good practice>> but I think the way it (and the overflow teeth) is designed makes it really unlikely to be blocked by a snail or other. <<Probably so, but...>> Maybe if someone didn't do their maintenance, enough algae could build up to slow it down. <<Yes>> So here's another tip that I just remembered: I cut a scrap piece of opaque black acrylic sheet to lie on top of the overflow, and cut it big enough so that it shades the entire overflow area from the tank lights. I used to regularly scrub algae growth from the overflow teeth and from the inside of the overflow, but since it's been shaded there has been no more of that. <<You make a good point. The overflows are typical built from an opaque material for this reason...but few folks think to cover/protect them from 'above'>> Thanks,
<<Be chatting my friend. EricR>>

Standpipe Mods...Keeping the Peace - 09/17/06 Hi Crew, <<Hello Tom>> I have a 135G acrylic reef tank, 25" tall, with a built in center overflow.  In the bottom of the overflow there is a 1.5" bulkhead (drains to sump via Durso standpipe) and a 1" bulkhead (return from sump).  I'd like to change the 1" bulkhead to be a 2nd drain directly into a new fuge section, while the 1.5" remains draining into the skimmer section. <<Sounds like the "new 'fuge section" is part of the main sump, yes?  While you can do so, it is not "necessary" to feed raw tank water to the refugium...there will be plenty of excess nutrients that will escape the skimmer section of the sump>> Both sections would combine to the return section with an upgraded 1000GPH return pump...the new sump w/bubble traps should be able to handle the higher throughput. <<Mmm, yes...but will the returns?  I'm gonna guess you'll get about 600gph through the 1.5" bulkhead and about 300gph through the 1" bulkhead before things start to get complicated/noisy.  So you are correct...with head loss (and the addition of a gate-valve on the output side of the pump) a 1000gph pump will be about right>> The old pump is 500GPH.  In the new setup I think I want about 1/3 of the flow to drain to the fuge section, 2/3 to the skimmer section. <<Is about what you will get>> The new return pipe would run up and over the rear of the tank. <<Okay>> All this is pretty straightforward, but I want the drain(s) to remain quiet. <<Indeed>> A 2nd Durso won't fit in the overflow. <<Mmm...>> And the current Durso won't remain functional with another drain in the bottom of the overflow.  How would you go about it? <<Well Tom, I certainly understand about wanting to keep things "quiet", and using plain unmodified standpipes rarely gives this result so you will need to use some kind of "silenced" rig.  Ken Stockman developed a design he calls the Aqua-Silencer (formerly the "Stockman Standpipe") which is purported to be just as or more quiet than the Durso Standpipe, but takes up less space in the overflow chamber (originally developed for use with the smallish siphon-overflow boxes).  Premium Aquatics sells a model to fit 1" bulkheads, and you could easily DIY one for the 1.5" bulkhead (or for both bulkheads for that matter!) yourself based on information available on Ken's site http://home.nc.rr.com/stockmanreef/interest.htm).  This standpipe design also looks to be aspirated, which may give you a few more "gallons-per-hour" if needed/wanted.  So, see if this standpipe design solves your problem...if not, give me another holler if you like and we'll brainstorm the possibilities.  That's how I would go about it...>> Thanks, Tom <<Regards, EricR>>

Overflow Noise/Glass Scratches - 08/15/06 Hi, <<Hello!>> I have a 54G RR Corner tank with a 1" drain and a 3/4" return. <<Sadly undersized throughputs...even on this volume of water>> I bought the whole reef set up used, but I can't imagine how the previous owner tolerated the noise! <<Mmm, indeed...you can't really put much water through a 1" drain before it becomes problematic>> I installed a 1.25" Durso standpipe (1" did not work, now I follow directions, doh!).  I have a 1/8" drilled hole in the top of the T of the Durso.  It was fascinating to watch the relationship between the air hole size, the drain line position relative to the sump water level, and the gurgling and flushing effect. <<Ah yes, you are finding out just how "fiddly" it can be.  I would like to suggest you try enlarging the hole just enough to push some airline tubing through and down in to the standpipe.  This will help with aspirating/releasing air from the drain line and often eases the gurgling sounds.  It will take some experimentation to determine the best length/diameter tubing to insert>> As I slowly increased the air hole from a pinhole up to 1/8", I observed the step by step decrease in flushing effect amplitude.   <<Yes...allowing that air I mentioned to escape more readily>> It started at about a 3-inch oscillation, at 1/8, it was gone completely.  Adjusting the drain pipe position also impacted the flushing effect and required small changes in the air hole.   <<Pretty much all comes down to eliminating the obstructions (air bubbles) to the water flow>>    OK, on to my questions:  I have extensive bubbling/gurgling noise in the sump from the drain. <<From air that is "carried" down the line by the water>> I have read on WWM two things to try: A "T" or "Y" fitting on the drain line, and aspirating the drain line from the top with air line tubing. <<Yes indeedy...though I prefer a 45- or 90-degree ell fitting on the end of the drain line>> I am confused about the specifics of both of these.  For the T or Y fitting, how is it positioned? <<Is of little consequence...just position to direct flow in the direction you desire>> I am guessing that it goes at the bottom of the drain line, with one leg submerged and one leg above the sump water level? <<Mmm, okay...I think I'm with you now.  The purpose of the fitting on the end of the drain line is to "slow" the rush of water a bit.  So...experiment with the position to determine which gives you best results.  Either way you position it, I find that having the end of the drain line completely submerged usually works best.  And do be aware, it is usually not practical to expect a 1" drain to flow more than about 300/350 gph without much hassle and noise, as you seem to be experiencing>> For the aspiration tubing, is the tube supposed to have its own hole separate from the existing air line in the Durso T cap? <<Refer to my earlier comments re>> Or does it simply go down the same hole? <<Yup!>> It also seems to me that the bubble/gurgle would be reduced if I had the water break on some live rock rubble or other irregular surface. <<Can give it a try>> I think I have seen reference to using filter pad material. <<A detritus trap>>   Next question: Even though I only have about a 2-inch drop from the overflow wall to the top of the water behind it, it still makes an annoying, trickle noise that induces the need to visit the bathroom at night (tank is in the bedroom). <<Hee!>> I am thinking of installing some kind of stepladder down to the surface.  Or perhaps a piece of filter pad would also suffice.  How have you seen this done? <<Raise the height of the standpipe to raise the surface of the water in the overflow...it only needs to "fall" a fraction of an inch or so>>    Last, the tank is used, and has a good number of extremely fine scratches that are visible depending on angle and lighting.  I have read that you generally shy away from glass polishing/buffing, but that usually seemed to be because the emailer was asking about significant/deep scratches.  What do you think about using a commercial buffer on an orbital drill pad, and follow with a thorough cleaning? <<I think you'll do one of two things...nothing at all...or make it worse.  Scratches in glass "can" be repaired/removed, but unless you really know what you're doing/have done this before, I recommend you refer to a professional for advice/consultation.  You may find it is easier/cheaper to replace the tank...or learn to ignore/accept the scratches>> Jack <<Regards, EricR>> Durso Standpipe in an external (hang on) overflow box   1/31/06 Hi, <Howdy> I have a 1 1/4 DIY Durso standpipe in an hang on overflow box.  I purchased the overflow box from my LFS.  The box did not lose siphon in a simulated power outage before I  installed the Durso, but now it does. <Yikes, or potential yikes>   The water is siphoned from the inside chamber too fast and siphon breaks.   <Yep> I have tried to extend the U tube way below the intake from the Durso, but to no avail. I can't even get the U tube to hold siphon with the power off.  It seems there isn't proper equilibrium between the inside and outside boxes. Any advice is appreciated, Thanks! <... Well, there are plumbing arrangements that can be fashioned as a work-around repair here, but they require a bunch of space... more than you likely have. There are other solutions... that call for something other than the Durso you have situated here... and these are posted... you guessed (!) on WWM. Bob Fenner> - Setting Up a Durso Standpipe - Hello, I went yesterday and bought all the parts for the Durso standpipes. I have a 1" bulkhead and got all the parts according to the instructions. Problem, I just assumed these items would fit into my overflow, they didn't. I think I might be able to get the 1" PVC, street elbow, tee to fit inside, but the 1-1/4" will not fit for sure.  <Ok.>  I read on the website that using 1" PVC is not effective, my tank is roughly 60 gallons.  <One inch should work... given the fact that you probably won't have nutty recirculation on a tank of this size... would certainly experiment - glue the T-fitting and street elbow together and just press fit on top of the stand pipe... see how that works for you.>  Any suggestions on reducing the noise?  <Give this a try first and see how things go... if your tank is still noisy, do read through the plumbing FAQs... I've posted a couple of different solutions there.> Thanks, Rajiv "Mickey" R. <Cheers, J -

Drain Pipe Diameter 11/3/05 I just started reading your site and have learned quite a bit in a short period of time. You mentioned going to Reef Central for calculation of drain size. For 1200 GPH they recommend 1.43 inch minimum drain pipe diameter and 18 inches of linear overflow size. <I'd recommend at least two 1.5" ID diameter lines for 1200 actual gph flow> In the various responses to articles you seemed to recommend for a 120 gal tank and the above flow rate 2 overflows with 1" to 1.5" of drain diameter. I know that more is better but could I get by with a 6" x 8" center overflow box and one 1.5" drain or do I need to go to a 2" drain. <The two inch> I don't want to put more than one drain hole in the overflow because I want to use a Durso or Stockman standpipe and having 2 in one overflow makes it more difficult to debug problems w/ the standpipe. Also, both Durso and Stockman only offer the standpipe for a 1.5" bulkhead. <You can make these...> 2" may be too large for a standpipe. <... uh, no> Having one center overflow will make it easier to design and build a closed loop manifold so I don't have to go around to corner overflows. <Understood> Thanks for your time <Thank you for your participation. Bob Fenner>

Durso Standpipes 7/15/05 Hello Crew! <Tim> I finally have my first reef aquarium plumbed and filled with freshwater for testing. I have a 135G from glasscages.com with two overflow boxes, two 1 1/2" standpipes flowing into a 55g all-glass converted to a sump/fuge, and a Dolphin AquaSea 2100 pump. I have Durso's in place which greatly reduced the gurgling up on top, and have just hacked apart my drain lines to put in a TEE style air vent as I have read about on your site. The vent did not seem to effect the rumbling rolling boil of bubbles in my sump hardly at all. <Mmm, you may have to adjust the aspiration... by lowering the small diameter tubing fed down the holes...> I was playing around and found that if i removed the Durso's from the standpipes, I could slide scrap pieces of acrylic over the tops of the standpipes and slide them side to side to "tune" them to the correct flow. Now, there is no way in hell I would leave the room with the tank running like that for fear of overflow, but AHHHHHH HHH what beautiful silence. Is the Durso TRULY the BEST way to quiet the gravity drain system down? <Mmm, no... but this discussion is very hard to have on the Net> As an engineer it is driving my nuts that neither I nor anyone else seems to have been able to solve the problem. Thanks for listening... Hopefully you can point me to a miracle! -Tim (A new aquarist drawn into the reef hobby by the information on your site) <Yikes... am luckily not a westerner by history, training... hence don't feel guilt re... Keep looking about... there are some works in print (by aquarists who are/were engineers!) that describe "other technology". Bob Fenner>

Re: Durso Standpipe of ayer, now I read the below yesterday on the FAQs.  As I'm planning a 90 gallon with one inch diameter overflow holes, let me make sure I understood. What I think I hear being said is that the Durso standpipe should be 2 inches in diameter with respect to a one inch diameter drain hole as this will make it run quietly.  Is that it?  Thanks.   <Yes, this is one approach... to be clear/er... if these lines are over noisy, oscillating in their flow, they are likely under-sized altogether... that is, the through put size, number may need to be larger... as well as the diameter of exhaust lines... to aspirate (adequately) the given flow. Bob Fenner> "Durso overflow Hi, I'm new to the SW aquarium community, I found this site is extremely help. <Change in tense> Yesterday I tried to DIY 1' Durso pipe to reduce the my 90G <... better to use 1 1/2 or even 2" here> Saltwater tank overflow noise. The Durso pipe works better than the old one. however, I can't reach the balance water level in the overflow chamber. It keeps up and down. <Ahh, larger pipe my friend> I tried to drill several 1/16" small holes on the vent cap, the water level keeps up, but never keep at the same level. Did I miss something here? Thanks, Jerry <Just the diameter of your conduit. Bob Fenner>"

Re: Durso overflow today Thank you very much for quick response. I followed "<Ahh, larger pipe my friend>", did a 1 1/4' Pipe, and drilled a 1/8" vent hole. All of sudden, the noise is gone. The water level in the overflow chamber stays stable, no "flush effect". <Heee!> What a tip. BTW, I tried Pipe size at 3/4', 1', none of them worked. Jerry <Easy, eh? Bob Fenner>

Re: Durso Standpipe tomorrow Ahh.  Then I guess if changing the drain hole(s) size isn't an option, and beyond the standpipe size, then one should primarily just be thoughtful in selecting how much water the return pump will move. <Mmm the enlarged size outside the tank can be of help... in aspirating lines... Please see today's FAQs re...>   That is, simply scale down your pump, provided that doesn't severely limit the water being turned over relative to the tank size.  Jon <Will reproduce the bit am referring to: Re: Durso overflow Thank you very much for quick response. I followed "<Ahh, larger pipe my friend>", did a 1 1/4' Pipe, and drilled a 1/8" vent hole. All of sudden, the noise is gone. The water level in the overflow chamber stays stable, no "flush effect". <Heee!> What a tip. BTW, I tried Pipe size at 3/4', 1', none of them worked. Jerry <Easy, eh? Bob Fenner> <<Slower flow, circulation through plumbing is one approach, enlarging lines outside another. BobF>>

Durso overflow Hi, I'm new to the SW aquarium community, I found this site is extremely help. <Change in tense> Yesterday I tried to DIY 1' Durso pipe to reduce the my 90G <... better to use 1 1/2 or even 2" here> Saltwater tank overflow noise. The Durso pipe works better than the old one. however, I can't reach the balance water level in the overflow chamber. It keeps up and down. <Ahh, larger pipe my friend> I tried to drill several 1/16" small holes on the vent cap, the water level keeps up, but never keep at the same level. Did I miss something here? Thanks, Jerry <Just the diameter of your conduit. Bob Fenner

- Need Some Opinions - Hello Bob.  <Hi, JasonC here in his stead.>  I'm in the process of setting up my acrylic 48"x13"20" reef tank that's been down for a few years due to moving and busy schedule. Am redoing the stand and hood too. Our living room looks like a workshop :) Would like someone to hold my hand as I venture forth with some plumbing advice/preferences. Technology has advanced a bit while my tank sat. The aquarium has one 5"x5"x19" corner overflow with a 1" bulkhead in the bottom, returning to the almost finished sump/refugium I am now making. My intention is to: 1) Drill another overflow in the opposite corner matching the existing one making two 1" bulkheads (large enough or drill them out to 1 1/2"?) using Durso stand pipe technology.  <Two one inch drains on this tank will be fine.>  I noticed on the Durso web sight that the stand pipe seems to only come in 1". Is there a reason?  <Yes... is the most common hole size drilled in glass tanks for the drain. Can easily build a 1.5" Durso-style stand pipe... have a self-made one in my tank.>  Will have 3/4" to 1" (preference?) return lines come up through same 5x5 boxes.  <One inch would be best... will give you better opportunities to upgrade the pumps, plumbing.>  Perhaps employ a squid valve to these return lines and a sea swirl (if needed) in the middle of tank on a separate pump.  <Sure.>  Am worried about water velocity hurting critters using a squid that will isolate return pump to only one line at a time. Valid concern?  <Nah... these have proven to be very good as water flow devices and in fact the switching back and forth is much better than a single point source that doesn't move.>  Was thinking of a pump that does around 1000gph. Good #? Pump recommendations?  <I'm partial to the Iwaki pumps, but there are many others that will work just fine. If you go for the bottom of the price scale, do yourself a favor and buy two, for redundancy's sake.> 2) Make a new, longer, center back overflow wall, say 16"x4", for improved surface skimming and looks. If I go with this option, I will either drill two bulkheads in the bottom and utilize the Durso stand pipe arrangement, (how big) or come in from the back of the tank up by the water line with two 2" bulkheads.  <If on the back, two 1.5" bulkheads would be fine - if in the corners, then 1" would be fine as well.>  The return lines have the same options, up through the bottom or in from the back.  <This is a call for you to make - it's your aesthetic that you need to please. No functional difference between the two.>  My worry with having bulkheads up high without stand pipes is noise. 2"ers should be plenty for 1000gph though, true?  <Two one-inchers would be fine for 1000 GPH. You are likely correct that any size vertical bulkhead used as a drain will be a little noisy.> Just bouncing these ideas around in my head, trying to think of all the + and - .  <No worries.>  Would appreciate any feedback you have on what might work best.  <Think you're on the right track.> PS: Am thinking of getting a new skimmer. The Aqua C caught my eye. Is it worth the $?  <Is what I own... think they are well worth the money.>  Also thoughts on a calcium reactor? Never had one.  <If you're planning on clams and/or stony corals, then this is a must. Otherwise, a good accessory to have but not a "must have" - am partial to the Knop reactors.> Thanks for the help, One who has definitely got the bug going again, (just ask my wife) Jim <Good stuff. Cheers, J -- > 

Diagnosing A Durso Standpipe Problem... I have checked the freq asked quest.  But still need assistance. I have a 75 gal with one overflow box with a diy Durso standpipe made out of 1 1/4 in pvc with a 1in threaded reducer connected to the 1in bulkhead opening. This drains into a diy 20gal ecosystem sump via a 18in drop thru 1in pvc. The outlet is aprox 1in  below the water line when the water is flowing. Problem is too much noise created by the air that gets sucked down the standpipe it really gurgles when it empties into the sump. I have played around with this a lot but I haven't figured it out.  I also have a larger air hole in the cap than recommended( 1/4in dia. as opposed to a toothpick size hole or gradually larger).  Anything smaller caused the overflow to slowly flush up and down.  Is there anything I missed?  Is there any way to make this less noisy?  I know that this will not be silent but any thing will be better than the present conditions. Thanks, Kevin V. <Well, Kevin- The Durso Standpipe is a great design, and really is relatively silent...I'm at a loss to explain, myself- so I'm going to recommend you contact the man himself. Richard Durso's website is: http://www.rl180reef.com/frames.htm Shoot him an email and I'm sure that he can offer some suggestions...Hope this helps! Regards, Scott F>

-Overflow Dilemma - Dear Bob: <Actually, JasonC today...> It's been several weeks since I e-mailed you but I have another question that I have been unable to answer.  I have just about everything ready to go for a new 180 gallon marine aquarium (FOWLR) that I have been setting up. With your input I decided to purchase a Euroreef CS8-1 Skimmer as you may recall from my prior e-mails.  It will be placed in a 50-gallon sump in a stand beneath this aquarium.  My question deals with the tank itself.  It is from All-Glass Company and features two corner overflows (not the newer center-located overflows that are found on their newer tanks).  The Mega-Flow Overflow Kits that the dealer sold with this tank are a tight fit since All-Glass now uses the Durso standpipe system because of noise concerns, etc.  As you know, these feature a 1" bulkhead fitting in each corner and a 3/4" PVC return line.  The numerous postings on various websites regarding flow rates for this and other drilled setups has my head swimming!  The nice folks at All-Glass indicated that each overflow can handle a flow rate of 600 gph -- 1200 total for the tank.  The many letters I have read seem to present a different picture, indicating flow rates as little as 200 to 300 gph. <Nah... a total of 1200 GPH is about right.> I have a Mag 18 ready to use for the return plumbing to the tank.  I made this choice after calculating flow loss due to friction and head pressure through the 3/4" return plumbing.  The return line will use a 'Y' connector to split the flow path and eventually bend thru the 90 degree elbows near the top of the tank.  I estimated a return flow of about 820 gph -- or roughly 410 gph for each return line.  Based on the lower flow rate numbers from above (draining thru the 1" bulkheads) I am now concerned that this pump may be too powerful.  If this was your setup would you install a ball valve to control flow? <I'd install one for other reasons... being able to take the pump out to service it, etc. But again... I think you'll be fine with your pump selection.> I'm not sure how mag drive pumps can handle any type of back pressure, so I'm reluctant to do this. Or, do you believe these overflows can handle a Mag 18 without interruption? <No worries.> Just to note the Mag 18, according to the manufacturer, has a flow rate of 1200 gph at 5', and 825 gph at 11' (which is the figure I used).  Thanks for any advice you can offer. Sam M.      <Cheers, J -- >

- Bubbles and Noise, Please Help! - Hi all, Thanks for all your help in the past! I have a problem with bubbles and noise in my drain line. I looked in the FAQ's and tried the vent hole T technique and it did improve the gurgling but I still get massive amounts of bubbles, and it is LOUD. I really don't want to decrease my flow rate as the my future SPS won't appreciate it. Also, I am using a Durso standpipe, and have included pictures to help.  Do you have any suggestions to improve this drain? <Well, you can try a couple of things... you can put a small length of PVC into that T-fitting to extend it - it looks to me like you've got water coming out of there at the moment - that might help. You might also try substituting a Y-fitting for that T and putting it a little farther up the line. You can also try what I have done which is put a small length of air-line tubing from the standpipe down into the drain line, perhaps about 3/4 of the length of the entire drain. This takes some fiddling to get it right, but provides an air source to stop those backwash gurgles that occur every so often. There's no way to reduce to noise to absolute silence, but you can certainly get it to a tolerable level. Regardless of which solution you try, you're going to have to go through a trial and error phase with each. Be patient, you'll get it.> Thanks a lot! - Ryan <Cheers, J -- >

- Noisy Bubbles - Thank you very much, I tried moving it up and it let out more air and less water. I wanted to make sure that I am not trying to accomplish the impossible. Is it possible to stop most of the bubbles that come crashing into the sump? <Hmm... I don't think so. Just the action of the incoming water entering another body of water will induct air - you can try this with a hose and a bucket of water.> If it is I will find the right combination, but if it is not is there a way to trap them other than baffles? <Depends on the size of your sump - a large settling chamber in the sump will eliminate some, but likely not all.> Thanks again for your help. -Ryan <Cheers, J -- >

Durso Standpipe = Detritus? Hello WWM Crew, <Hi Maurice, PF here tonight> I have a 125 marine fish only tank and I've just cleared out my prefilter (mesh rolls) from my overflow boxes after reading some FAQs about the build up those things collect and what a nitrate heaven they are.  The water now runs straight to my sump over a bonded filter pad (which is much more accessible for cleaning) then over the bio balls. <Remember to clean that filter pad. Have you thought about using a PolyFilter instead? It would help pull pollutants out of your system> Now to my question, since I've removed the prefilter rolls from the overflow boxes, I now have a nice waterfall going, so I was planning to build a Durso standpipe (that I read about on your website, good idea) <I read about them here too, mine was a life saver.> in each of the overflow boxes to remedy this problem, however my concern and question is: with the water level raised being drawn from such a high level, won't you get a build up of gunk, settlement and detritus built up on the bottom? <I wouldn't think so. Depends on how high you build. You can make them lower if that's your concern. Nothing is written in stone as far as methods/procedures go.>  If yes how would you prevent this, if no why not? <I've not noticed any build up in my system, nor have I ever heard about this happening to anyone else.> Thanks as always for the great site and advice. Maurice <You're welcome, hopefully this clears up your fears.>

- PF Discovers the Durso - <Hi, Mike, JasonC here...> Until I read today's FAQ, I had never heard of one of these. I'm taking off from work early to go buy the supplies and experience this thing called "quiet" for myself. <Geese... you been living under a rock? ;-) Anyway, you'll find this design works quite well.> Thanks again guys! PF <Cheers, J -- >

Durso standpipe Hello, <Hi John, Don from NE with you tonight> I have 55 gallon fish/reef and am adding a 10 gallon refugium underneath. I have a bottom drilled tank which used to have a overflow stand pipe to the sump But very noisy!  I would like to use this to feed the refugium.  I search the Internet and located the Durso standpipe. It's an overflow pipe with a tee on top, continuing to a cap with a air valve mounted in. Out of the tee is a st. elbow into the water.  You can mount a strainer to the elbow.  They state that at power failure there would be no siphon to the tank below and no noise.  Have you herd of this method or is there another safe way to complete this. <Yes, many, many happy people using this design. Follow the directions for construction and you should be happy as well> Many Thanks, John from NY

3/4" Durso standpipe Dear Craig or Steve or ?? <How about David> I am losing my mind.    :-) <Prozac may help> Ok, that being said... I managed to  ditch my 55 gallon acrylic tank and archaic J-tube siphon overflow. I replaced it with a 55 gallon all glass tank that was pre drilled at the bottom left side with a 1" gravity fed drain and a 3/4" return. I got "hosed" when I fell for the trick and paid $59.99 for the  "kit" to hook the bulk heads up and the overflow.  The "kit" basically had two bulk heads, 2 barbs, some pvc tubes and a float (which is the biggest piece of crap I have ever seen). <Yep. I know what you're talking about> It made so much noise when installed that I had to remove the float assembly altogether.  There weren't even any adjustments that would quiet it down. not unless you know of any. ??? <Typical scenario for these package deals> Ok, so here's where I stand now.   I basically have the tank set up with sand and live rock...all fish are back in quarantine tanks as I had a case of ich one day prior to swapping tanks. >My overflow is making horrendous toilet flushing sounds, so I built a Durso standpipe for it tonight. <Ahhh...I built and use a Durso on my tanks. It don't get no better than a Durso!> It's now 5:10 and I haven't slept a wink yet, trying to fine tune this thing. <Yeah but once you get it working you will never need to do this type of adjustment again> I drilled a tiny hole in the very top of the stand pipe. on the end cap.  My hole is about the size of a toothpick. maybe a tiny bit larger, however the sound of the air being sucked thru that hole is atrocious, and if you don't have the hole "exactly" the right size, the flow in the intake bobs up and down and sounds like toilets flushing over and over. <Correct. Here's what I did: Start with the absolute smallest drill bit that you can find and gradually increase the size of the drill bit until the hole is perfect. Time consuming? Somewhat...but it works> I have a 1" pvc stand pipe, however due to the small dimensions of my overflow internals, I had no choice but to downsize to the "dreaded" 3/4" so the >U-configuration would fit, and it barely does.   <Uh Oh...I don't know what the ramifications of this move are. You're a canary in the mine on this one> My question is "Why am I hearing so much noise at both the overflow as well as the drain hose leading down into my sump?"   <My guess is the 3/4 ain't workin'. Are you absolutely sure that you can' make the 1" work? That would be the better option> I have a 55 gallon tank with a Mag Drive 700.  It's in the sump beneath my tank, connected on a 3/4" line shooting straight up thru the bulkhead and out to the return side of the overflow. <I follow> The intake side of the overflow/skimmer area has the typical Durso standpipe configuration but I had to use the 3/4" fittings going all the way down to the 1" bulkhead where I had to put a coupling to connect 3/4" to 1". I've been reading on the net that that could be my problem, the fact my drain tubing is narrower than 1" in the overflow area. <Well, from recent experience (the last 5 years) I can tell you that the Durso was amazingly easy to assemble and install. The whole process including going to the store, getting the parts, assembly, installation, and fine tuning took about 2 hours. The operation has been almost perfect since that day. You just need to clean it occasionally> It is evident that my sump pump is blowing air bubbles into the tank because it's pumping more water out of my sump than the overflow is flowing into the sump. <Sounds like your pump is too strong.  Does this occur with or without the Durso? I suspect that 3/4" fitting is too restrictive for your pump. You may need to look for another design > Should I purchase a ball or gate valve for my pump so as to reduce water flow to the tank? <That would be one way of dealing with it> ..hopefully slowing things down enough for the 3/4" overflow standpipe dealie to catch up? <I won't guarantee success but it's worth a try...and not very expensive> Man...I'd appreciate ANY info you can give me on my specific problem.  I have a "standard" 55 gallon tank with the "Standard" left corner overflow siliconed in black all the way down the corner of the tank.  It's too tight to use the 1"+ pipes and fittings called for in the Durso stand pipe config, so I used 3/4" Was wondering what I can do to reduce-eliminate noises from both the overflow and the drain tubes which are 1 1/4 sump type black hoses. <Yeah...I'm afraid your problem is the relationship between the plumbing parts. This 1 1/4" is adequate for your tank it's the other plumbing parts that are too small...especially the Durso. If you don't get this problem solved soon, email again and I'll forward the message on to another writer that might be of more help> Good lord I babble too much. <Don't we all> It's late and I'm delirious. <It's now early and I'm delirious!> Please help. Steve <David Dowless>

3/4" Durso standpipe Dave, I still haven't slept a wink.  Just came back from Home Depot with some ball valves. I put a 3/4" ball valve right after the main pump in the sump, headed up to the tank (the return line).  I closed the valve a little bit to reduce water flow by maybe 20%. I then installed a 1 1/4" ball valve on the drain hose leading from the overflow into the sump.  The ball valve is about a foot away from this hose's exit onto my filter padding, etc.  I closed this valve about 40% and that seems to have quieted the gurgling sounds coming from the overflow hoses, so far. <Great!> You aren't going to believe this, but right now the 3/4" pvc tube that I temporarily am using as my standpipe, is STUCK, in the bulkhead and I cannot get it out.  I am afraid I may break the tank bottom glass. <IMO this is a possible scenario. Handle with care!> I already tried to pull the tube out about 10 times and used every method under the sun.  During one of my test tries, I must have put it on too tight and now cannot remove it. <I assume this 3/4" pipe is screwed into the base? I have also had difficulty removing this item on occasion. Twist from the top and try not to favor either the left or the right side. Apply the pressure evenly and gently. As long as your not rocking the pipe or pulling on it I can't imagine that it would break the tank. No rocking, no pulling...Just apply even pressure as you turn. It will come loose> So right now I'm using the 3/4" standpipe configuration.  I drilled the smallest hole u ever seen, on top of the unit and it is still making this sucking sound and the water in the overflow area keeps going ALL THE WAY UP , right up to the hole, then I hear it gurgle, then it comes down real fast to  the lowest point where it nearly loses it's prime. <Exactly. This is familiar to me and to be expected. The problem? The siphoned hole in the top of the pipe isn't large enough. Use a series of drill bits going from small to larger. Drill one (like you have done) then if it doesn't solve the problem, get the next size bit and widen the original hole. Then replace the pipe and see if that works. Continue this process until you find the right size hole for the pipe. You will know instantly when you get the right size. Suddenly you'll go from hearing Niagara Falls to sweet silence> It's the "back and forth" water movement that I can't seem to figure out.  What causes that? <Not getting enough air so that siphon breaks. When the size is correct you will have a constant water level in the overflow...no seesawing> I'm going to drill a tiny bit larger hole now, then I have to shut down and go to sleep....long frustrating week with this tank. <Tanks can be and often are frustrating, exasperating and will make you say words that you never thought you would say! When people visit at our house, they frequently comment on the tank and how they have often wanted a saltwater tank. I always tell them that it's a lot of work (there are NO maintenance free systems and I don't care who tells you otherwise), and there are no inexpensive systems. In order to succeed you must love/enjoy what you are doing. Kind of like golf: The tediousness is pleasure to some and pure pain to others...depends on the personality. Take a break, get some sleep, have a beer, etc, things will get better!> Please feel free to forward this mail to anyone u think may be of assistance. Sleepless in Florida, I remain <If it makes you feel any better, I've had the strep throat for 3 days and it's 4 in the morning. I can't sleep either! Let me know how this turns out please. Feeling your pain in Las Vegas, David Dowless>

Re: 3/4" Durso standpipe Dave, Wanted to thank you so much for the advice, although it came two days late. <Darn. It took me that long to answer your email? Sorry about this my friend. I'm normally much faster...> I was able to remove the 3/4" pipe from the overflow and install a 1" diameter pipe instead. <YeeeHAW!!!!> I drilled the hole in top of standpipe just a tiny bit larger, and everything is now quiet, as well as adjusting the ball valves on both the return and overflow lines to slow down the flow, decreasing gurgling noises even further. <Ah yes...silence. What a wonderful state of being...> The tank is up and running.  Now I need to plum in the refugium.  A few more 6 packs and I should be there. <HAHA!> I'd like to send you a photo of my tank, when it's completed. <I'd love to see it. Do send> I just don't know when I email ya's, who exactly is going to be replying. <Put my name in the subject line> It seems there are many many people volunteering? <Au Contraire...7 total including myself and some WWM crew members only answer very specific questions. We get 50+ emails a day, sometimes many more. It's not a small task, but enjoyable> This is volunteer work no? <Yes. But we do meet wonderful people and we are helping to save critters lives! A worthy goal IMO. WWM also gives aspiring publishers ($) such as myself contacts within the industry> Is "wetweb" an actual place where people work? <Not exactly. The name and website is the vision and creation of Robert Fenner, who owns the name and company... but there isn't a building called "Wetwebmedia." For all intents and purposes, WWM is a publishing and content provider company that exists in cyber space only. The cost of the website, and it is expensive, is paid by the advertisers that you see on our pages. The profits from this venture are then sent back through the company to pay for our publishing efforts (Have you seen the new WWM book?) and other "company" related things. While it may be hard to believe, each of us answering questions reside in different parts of the country: I'm in Las Vegas, Bob lives in San Diego, Anthony lives in Pennsylvania (I think) etc. The wonders of the web!>. Another question....the black plastic separator at the top of all glass tanks.  It's casting an ugly shadow in my tank from the halide lamp above it.  The plastic seems flimsy and I'd love to cut it off.  Has this been done before?  Is that flimsy piece of black plastic in the middle of the glass tank top, a structural piece?  I just thought it was there to support a lid and some flimsy lights. Please ask around if it'd be ok to cut the piece away so the entire top is unobstructed. <If you must, proceed with caution!> Thanks again for all the advice. <My pleasure! It's a relief to know the problem is solved. David Dowless> Steve

Re: 3/4" Durso standpipe I wrote: Ok, so now I put the 1" Durso standpipe on there and the flow is much much better.  I drilled a 1/16" hole and farted around with the return flow and overflow discharge ball valves to get them sort of in sync with one another.  Things seem ok, although now I'm having one problem with air shooting out of my return fitting that's about 2" below the surface of the water.  Air is shooting out under the water when I "power up" the system and the pump shoots a wad of pressure out all at once.  So water and trapped air shoot out of the tank and go about 2" high and I'm afraid it will splash on my 250w Metal Halide bulb. You replied: <Use a valve to turn on the water after you turn on >the pump. Purging of air and such is normal. Just get >up to flow slowly.> Craig. everything is on a timer.  So many things going on/off at different times.  I cant be there when a power failure occurs.  Remember, this problem only occurs when the power goes off and then back on in my absence.  I wanted to know a way, perhaps, down in the sump. over the pump where I can install some type of air release PVC uplift section where air escapes as water is drawn down into the sump.  Please advise. <Ah yes, sorry. I see. Honestly, it's best to shield your bulb from any possible splashing. The air in the lines really can't be helped that I can see. If water vacates, air will fill the void. When the pump comes back on, it will be expelled pretty forcefully.> Regarding the tiny hole drilled in the return line: You wrote: > <You want this, although the hole should be below > water level when running, and above when the power > is off. This is to break the siphon between the main > and the sump or your tank will siphon until the sump > overflows......> The water in my overflow, when tank is running, is about 3" lower than the main tank water.  When I turn the power off, that level remains the same in the overflow, as the tank water slowly siphons down thru the overflow's skimmer slots, yet the overflow level remains constant at 3" below main aquarium.  It doesn't rise/lower.  So where should I drill the hole in the return?   <Yep, you have those lovely All-glass overflow boxes... Think camels, beer and e-lax.  Anyway, the holes go in the PUMP return lines to the tank if they go below the running water level or below the level of the all-glass overflows. In the event of an outage, the water is going to drain to the top of the all-glass overflows no matter what. If the *pump* return line is below this level, *it* will than siphon water through the pump, unless the return lines have small holes at the water level of the all-glass overflows. Phew! I hope this is clear! If not fire me another post...!> Thanks again. I just need clarification. Steve <No problemo, dude! Just let me know if you need more!  Craig>

180 Overflows Thanks for all of your past counsel. It has proven accurate and helpful. <We are glad to be of assistance.> I have a 180 gallon Oceanic Reef Ready tank with two overflow boxes. I currently have a Little Giant 4MDQX pump for the return from the sump, rated at about 1100 gph. I'm considering upgrading to the Iwaki MD-70RLT which is rated at 1800 gph. I have 26 gallon Lifereef sump, as well as a Lifereef skimmer in the sump which is operated by a Little Giant 3MDQX rated at 810 gph. I am currently not having any problems with "sucking sounds" coming from the overflows. First of all, would I have any problems with the Iwaki 1800 gph pump given only the two 1" overflows? <Possibly, but could be overcome with Durso overflows modifications or other possibilities. Do take a read through our archives on plumbing issues on www.WetWebMedia.com. I would use the Google search engine looking for the terms reef ready and overflow boxes.> Oceanic says between 7-10x the tank's volume and I should have no problems, but I wanted to get your opinion. Also, is the Iwaki a quieter pump? <They have that reputation.> Thanks, Marc <You are welcome. -Steven Pro>

Stand Pipe Hey guys. Searching FAQ's and all over the internet for a good answer to a question I have and couldn't find one but here goes. I am in the process of plumbing my 75 gallon tank. I have two 1.5" holes drilled along the back with bulkheads, which flow to the sump in the stand below the tank. I am worried about the noise of the water draining. From my understanding and reading, the standpipes (Durso) are for overflow boxes or predrilled overflows on the bottom of tank not for the back with bulkheads. IYE, what can I do to eliminate or prevent that gurgling, sucking noise? <I vent the drain pipe so that the air can escape. Instead of using the elbow that comes with most bulkhead kits, I attach a T so that it is aligned perpendicular to the ground. Water comes into the T and falls straight down while the air escapes up.> The only thing I could find was where someone took and drilled a hole in the PVC on the top of the bend (elbow) going down to the sump. Then siliconed a piece of airline tubing about 3-4" down the PVC and left a few inches sticking up the top of the elbow. <A similar method of venting away the air.> Please let me know. Thanks again, Bryan <You are welcome. -Steven Pro>

Durso Overflows Thanks for your quick response. I will do as you recommend. Two more question please: 1) I have a 125 gallon All Glass tank with the 2 overflows in each corner. I was reading last night about the plumbing you recommend for the water going out of the tank down to the filter. It was called Durso? <Durso actually, for Richard Durso, the man who came up with a solution for a noisy overflow box.> Where in your site can I find how to assemble? <Richard Durso has his own website with excellent instructions. I do not see a link to his site on our links page. I would just use a search engine using the keywords Durso overflow.> I was told by two local aquarium stores to simply use bioballs on top of eggcrate in the overflow. <It would work to quiet the noise, but would also trap a lot of detritus.> 2) How may ball values do I need in the plumbing and where. <One before and after pump for servicing.> I saw your diagram by Anthony Calfo has one before the pump and after the pump, but I was thinking to put one in each line after overflows before the filter <It is not a good idea to restrict your overflow water. This should be a nice gravity flow down to your sump/filter.> and one in each line after the pump and after the Y split going back to the tank. <For controlling the water from multiple outputs, gate valves are much better due to their finer control, but more expensive and harder to find.> Thanks, Steve <You are welcome. -Steven Pro>

Durso Standpipe Hi Guys I have an Oceanic 105 reef ready tank and have the usual problem with the overflow box. I filled the box with bio balls and foam blocks and while I had my old pump it was nice and quiet. I switched to an Iwaki 30 and the noise began. The return line to the sump has a continuous air/water mixture noise. To combat the noise I constructed a Durso standpipe. I drilled a 1/16th hole in the end cap and lo and behold, the noise continues and the water level in the skimmer box is as high as the tank water. I made a 5/64 hole and the situation got worse. When I closed the hole, the sucking noise got worse. I now have the pipe with a 1/16 hole and the noise is driving me crazy. What am I doing wrong. <I suggest you check out Durso's personal page. He has a few suggestions and potential pitfalls listed. The "Build Your Own Standpipe" page had some good info. He uses frames, so I cannot give you a direct link, but start here http://www.rl180reef.com/frames.htm and look around. One thing that stuck out to me was his recommendation to use 1 1/4" or 1 1/2" PVC pipe into a 1" bulkhead drain.> Thanks as always. <You are welcome. -Steven Pro>

Aquarium noise Hi: I hope you can help. We just set up a new salt water 180 gal oceanic reef ready aquarium. It's set up in the den, so we did everything we could to keep the pumps etc. on the quiet side. All that was for naught because you can't hear the pumps, protein skimmer or even conversation ( well... maybe not quite that loud ) because of the loud splashing/gurgling coming from the overflow chamber. I tried inserting sponges where the water hits the bottom but that didn't work. The noise apparently is coming from the drain hole/piping instead of the water falling to the bottom of the chamber. Do you have any ideas on quieting that sucker down? thanks in advance Terry <Yes, a few... Consider building a riser out of a piece of PVC pipe that has slots cut in it (no need to get too involved here on what size, how many... you'll be able to pull out, modify as we go along...) and insert this pipe on the hole cut in your tank via a FIP fitting (thread to slip)... with the top open to allow for overflow... Am a bit tired... and don't know if this makes much sense... Some folks wrap these sorts of risers with batting material (like from the yardage store, and panduits/zip-ties... to strain out the larger particulate/suspended material as it passes through from the tank to the sump below. Bob Fenner>
Re: aquarium noise
Bob: I know about tired....been a long day. thanks for your quick response. We have the risers in the overflow boxes already, but I hadn't thought about wrapping them. The noise is definitely coming from the drain hole at the bottom. I was also thinking about cutting a piece of Plexiglas and gluing foam sponge to the bottom with a hole cot out for the riser, but I guess I could also put foam in the riser, since it goes all the way to the top of the overflow.  <Sounds good, just don't impede the flow too much, or allow a clog to occur... maybe a floating diffuser box on the entry side of your sump, with holes cut in the sides to allow the incoming water to flow out...?> I'd then use the Plexiglas to cover both boxes without covering the whole tank and avoiding gas exchange problems and increasing tank temps. thanks again. Terry <Good luck my friend. Bob Fenner>
Re: aquarium noise
Thanks again Robert: The tank came with foam cylinders to go around the standpipes...I'll just have to be careful to keep them clean. I have the diffuser box in the sump too. thanks for the advice. TP <Hope it all works out... have rigged the bottom "box and foam" design myself for quite large flow rates in holding systems, fish hatcheries... You know, another thought/idea comes to my feeble mind... have you seen the great filter bags offered by Emperor Aquatics? Fitting one of these (get two so you can be cleaning, air-drying the other while the "A" one is in service) on the discharge of your tanks overflow line will easily remove a great deal of particulates, quiet the water flow down, and be very unlikely to result in overflow of the sump... Yeah, just checked and their link is on the wetwebmedia Links pages... hunt these bags down... very worthwhile, Bob achooo Fenner>
Re: aquarium noise
Bob: I was surfing and found this link with what sounds like a perfect solution....at least from all the kudos left at the site. Look under hardware...then at the top of that screen look for the ....standpipe http://www.rl180reef.com/frames.htm terry <Great... will add to plumbing FAQs. Thanks, Bob Fenner>

Strainer for Durso standpipe I have a 1" Durso standpipe in my 75 Gal tank(1-1.4" wouldn't fit) and am having troubles with snails getting into it and clogging the drain line. Is there a strainer that would fit into my 1" street 90 and where would I find such a thing? Or do you gentlemen have a better idea? Thanks, Spence <There are threaded strainers... you can fit a slip adaptor as an insert... or add a bit of pipe and a slip by thread coupler (if there's room) to thread this in... You can buy these online from some etailers... Check with Marine Depot, Custom Aquatic, Aquatic Warehouse (.com). Bob Fenner>

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