Newbie Durso Pipe Question

So I just filled my aquarium with tap water for the initial run and leak test. No leaks!

I've got a 50 gallon cube with a 20 gallon sump. I have a 400gph return pump.

I have a question about the Durso pipe. Isn't it supposed to be almost silent? I have a 1" Durso pipe.

The Durso pipe is in the overflow, the water level in the overflow is about 2" lower than the level in the display tank.

The water level in the overflow is maybe a half inch higher up on the Durso pipe than the level shown here:


(Not an actual picture of my tank.)

The water level remains fairly level in the overflow box.

The problem is I hear a constant loud draining/gurgling sound coming from the Durso pipe in the overflow. I also have a lot of air bubbles coming out of the drain hose into the sump, and the sump area is very noisy with bubbles in the water.

I have a hose coming down into the sump from the bulkhead (it's not hard piped). The hose is currently down below the water level in the sump. Should the hose be above the water level so that the drain water splashes into the sump?

I'm thinking I need a ball valve in the drain line to the sump to slow the flow down a little?

 

OK I slowed the flow from the return pump to the DT and the noise is gone. My return pump has a flow adjustment on it, but I don't know how much flow I've got at this lower setting. Max flow is 400gph.

How do I know if the flow is too low? What is acceptable flow through a sump with a fuge?

 

Have you tried venting your standpipe? Dursos often need to be "tuned" for max quiet by venting the top of the cap, altho sometimes a slight flow adjustment is required as well.

We use Dursos on all of our sump-based systems, and they work very well once set up.

This is how I tune them:

Drill one 3/16" hole in the cap, check for noise. If still noisy, use your finger to partially cover the hole to various degrees. If it gets quiet, add an air control valve to the hole and adjust it. You can add the valve directly to the Durso and glue it in, or shove a small piece of rigid airline tubing into it, add a short piece of flex tube and then add the valve.

If one hole doesn't work, I stand there with my drill and add a second hole, then I repeat the process. I keep doing this until the standpipe gets as quiet as it can be via venting. Once I achieve this, I sometimes will play with the return flow a little to get it really silent. FWIW, I think the most vent holes I've added were 4.

Anyhow, I've been doing it that way for about 10 years.

EDIT: I looked at your photo again, and altho I can tell for sure, it appears that your standpipe may be "reduced down" quite a bit at your bulkhead. FWIW, we normally reduce them by 1/4" from standpipe to bulkhead (e.g., 1 1/4" pipe, 1" bulkhead). If it necks down too much, I suspect too much water may be trying to crowd thru the bulkhead if this is the case, and your best option would be to reduce the flow and try to re-tune until you find a happy medium between flow and venting.

HTH

 

DO NOT PUT A VALVE RESTRICTION ON YOUR RETURN TO THE SUMP!!!!

As soon as the flow is mis-matched- you WILL flood your DT and be mopping up SW!

There are many other ways to quiet this down- this way is not an acceptable one- for the health of your floor, any neighbors who may live below, and/or your marriage!

Like Greg stated, the cap needs to be vented first, etc.

 

+1 on the venting, That's how I have mine now and it is silent.

 

I realize that restricting flow from the DT to the sump is a bad idea.

The Durso pipe came with my DT and it has a rather large hole in the cap, about a 1/4" opening. When I slow flow to the DT from the sump by throttling my return pump, the noise is greatly reduced, and almost completely gone. Which is great.

However, this flow appears to be half of the maximum flow my pump is capable of. Full flow is 400 GPH, so I'm estimating minimum flow to be around 200 GPH.

Is 200 GPH adequate flow for proper filtration through the sump/fuge? Like I said I have a 50 gallon cube DT, and a 20 gallon sump. From all of my reading, I think it is enough.

 

Stick an airline down the hole in the top and very slowly work the line in and out and you will notice that it quiets down and gets louder, you need to find the sweet spot where it is quietest. Keep in mind it will quiet down a little more when the inside of the pipes get a bit of a slime coating built up after a few days.

 

I had the same issues with my set up and it drove me nuts! I also dialed back my return pump a bit and it made the difference. I found this easier than trying to fiddle with the air line and or drilling additional holes. If you slow down your return pump it will obviously decrease your flow in the sump which will increase the dwell time for your skimmer and huge which is not a bad thing as long as the flow is not too slow. You should be able to make up any flow loss in your display tank with using the right powerhead i would think.