Question for Durso Pipe users


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I have 2 Durso Pipes on my 120g. I have been noticing lately that the water level in my overflows keeps dropping. I had just finished tuning them and they were good for a week or so. I was about to break out the drill and make the holes bigger, when I noticed the holes were encrusting shut with salt creep.

Has anyone else noticed this problem? Is this common, or have I done something wrong?

Seems like every other day, I need to take a toothpick and clear the air holes on top of the Durso's, then the water level will rise to where they are supposed to be.

Is this a daily chore I will have to do, or is there something I can do to eliminate/alleviate the salt creep from forming? Also, my tank has only been running for alittle over 3 weeks.

Thanks David. I have two holes on top of each Durso. They are 7/64th".

Wouldn't I just have the same problem if I stuck a vinyl tube into the top of the Durso? Wouldn't salt creep get on it and start encrusting the tube shut?

I have seen what you are talking about before and wish I had done that to begin with. Very easy to adjust the airflow, no drilling or anything.
No, that's not the case. I should have been more clear. The residue is coming from inside the Durso pipe. I am assuming it is splashing up or bubbles are popping near the top and are leaving salt residue behind, which is accumulating on the holes, closing them up.
Lengthen the top piece between the "T" and the cap that has the hole(s) in it. That will extend the hole away from the water and potential salt creep. I have never had to clean mine out in over a year of usage... You probably only need an extra inch or so...
Yea, I guess that is my only option thus far. I just didn't want to raise the tops any higher than what they already are.

Maybe I an fabricate something that would protect the holes from spray, but still allow the air into the pipe. Maybe cut a piece of small PVC in 1/2 and attach it to the inside top of the pipe, so it protects the holes from overspray, but the ends of the 1/2 piece of PVC will allow air into the Durso.

I'll have to play around with it, but extending it sounds like the best plan so far.

I had the same problem until i just made the holes larger. I do not see t having the holes too large.

Does anyone know the drawback?
I had read about this before I started tuning and drilling out the holes. You get to a point where you start being counter-productive and it allows too much air in and starts making noise, flushing sounds and whatnot.

Not really a big deal, you just use some silicone or something to seal the hole up and start again. Or better yet, put some vinyl tubing in there and attach the adjustable air valve on top and that way you don't have to worry about drilling anymore, just turn a handle to adjust air flow.
What I have read and experienced has been the exact opposite. The smaller the hole gets, the less air it allows, the more vcuum like the standpipe gets- hence the flushing. When mine filled with salt creep, it didnt allow air and the water siphoned to the bottom of the street ell. It broke when it sucked air and started over again. I just incrementally increased the size of the hole until that didnt happen. The only difference I noticed was the water level was slighty up. The Durso website says you want the water like half way up the street ell, and mine is a bit higher, but with no side effects. I do not see that "too much air" can ever be a problem.
I think you have misunderstood me.

I agree with everything you said, except about having too much air. When you continue to keep drilling the holes bigger and bigger, you get to a point where you start creating noise b/c the holes are too big. So there is a point where too much air will start to cause other problems, b/c if it didn't, then why cap the top?

I was just replying to your question about drawbacks of making your holes too large.

My water level sits right at the top of the street ell on mine.
OK, well I agree with that. I am not talking about making a 2 inch hole in the top. But, the amount of noise you'll discern between a 3/32 inch hole and a 7/64 is going to be negligable and non-existant. But the amount of air allow in will be significant. I would suggest making the hole incrementally larger and larger until salt creep doesnt impede you anymore.
Problem is, I have 2 holes per Durso. So that's almost a 1/4" per Durso of airflow.

First thing I will try when I get some time, is to dremel the inside of the hole, to widen it out and smooth it out. Then hopefully, the salt won't have much to stick to.

If that doesn't work, I will try to either make the holes bigger, or just extend the piece of pipe connecting the street ell to the end cap, to give more room between the water and the holes in the endcap.

Thanks for the help though.
I dont think you be able to add a section to the street ell. The street ell is design to save space, so it tapers to fit. you'll have to get a 90 degree elbow and a small section, but i still dont think that will help.

Perhaps this is why the durso site says to only have the water half way up the ell? It lowers the water level to prevent salt creep. If this is the case, maybe making the holes smaller to "back pressure" the water level down. But I am just spitballing, now.
That's the way it was when I bought it. So I just went real slow and opened up each hole, till I was satisfied with the water level and the noise level. It has worked out fine, as long as I can take care of this salt creep problem.

Worse comes to worse, I can just buy new endcaps and start over.

Also, I just looked at a Durso Pipe pic, since I am at work and I didn't phrase my fix regarding lengthening pipe correctly. I would increase the pipe distance between the endcap and the T fitting. I shouldn't have mentioned the street ell. That way, hopefully, nothing will be able to reach the endcaps and I won't get salt over my holes.

That could be a possibility about where to have the water level on the ell, but when I had it there, the sound of the water falling and splashing around was too much for me, so I adjusted it to move the water level up and now it is whisper quiet. And if I wanted to lower the water level, then you are correct, I would just plug one hole on each Durso and the water will would drop down, but like I said, it was too much noise for me. So, hopefully, I can fix this salt creep problem and be able to keep my waterline where it is.
one last suggestion, then I'll stop acting like i know what i'm talking about. I would plug one of the two holes and then just slowly open one hole larger and larger. The only reason I am insisting on this technique, is because it is exactly what worked for me. Nonetheless, good luck.
The salt creep could not block the larger hole enough to effect the air flow, so it had no effect for me. And I could not detect any change in volume. FYI, part of my routine was when I had my canopy off, I would spray a little RODI water into the hole to dissolve any creep accumulating also.

It sounds a whole lot easier than adding a section of pipe, but that technique shoudl work also.
Alright then, I will give that a try first and see what happens.

Thanks for the help and info Jmaneyapanda.

I will update here once I get some time to tinker around and let you all know what I found out.

Thanks again,
I built twin durso into my overflow. The short straight vertical pipe on top is capped but I drilled a single rather oversized hole [3/8] through the side of both. Then by twisting the cap it can close or open the airway. As your salt creep problem changes, you could just twist open the airway. I do get outside salt but when I add change water, I just pour it over the durso like rain and salt slips away.
William Fisher
I almost forgot about this thread.

I hate it when people say they will come back and post the results of what they find, then never do, so you don't know what the solution was.

Anyway, I ended up replacing the end caps on my Durso's and drilled a singular 3/16" hole in each cap and raised the cap about a 1/2" on each side by not pushing the endcap all the way down on top of the Durso and all is well.

I was out of town all last week and when I came back Saturday, the tank looked great. The water levels were exactly were they were before I left in the overflows and there was no salt creep near the holes.

Just thought I would update for future reference.

Thanks all.