Durso standpipe help...

[Angela Short]

I have my overflows going and my standpipes (1.5" each) are doing the flushing like a comode thing. They were real bad and I kept drilling the air hole bigger and they are fluctuating up and down now but not violently like they were last night. The durso websight says this is due to backpressure in the pipes. I have a nic e even fall from the farthest pipe and it picks up the closest to the sump discharge via a tee. The overflow drain closest to the outlet has only about a 1' fall over to the sump where both overflows dump into the sump with the one 1.5" pipe. I have a nice drop on the pipes and the outlet of the sump isn't even under water to cause backpressure. Could I be getting the problem from the overfloe closest to the sump being tied in via a tee? Just dumping straight down into the water flow from the other farther away overflow causing a "log jam" of sorts of water causing the backpressure? Hindsite I should have used a sweeping tee I guess? If I have to replumb this its gonna be a SUPER PITB because my closed loop is all glued up in the way. UGG I am so over this tank, and I noticed even more of my corals are dyeing this morning . Any help would be appreciated.

 

[spjeff69]

How big are your holes? The directions on the website weren't that clear to me. I believe it says the more flow you need, the smaller the hole. However, when I turned my return pump all the way up, I had the flushing problem. I just made my whole bigger.

 

[Angela Short]

I think they contradict themselfs also on the site. I am getting fluctuations up and down like my hole needs to be bigger says one section then it says if your hole needs to be bigger the water level will just be to low.... It seems like the flushing thing to me but I don't see how unless the tee deal I explained. I may just keep drilling my holes bigger and just get new caps if it doesn't help...
Oh my holes are almost 1/4" but I only have a 1,600 GPH pump - head running both overflows so its pretty slow flow...

 

[rsteagall]

The more flow of the pump.. the larger the return has to be from what I remember.

I must have a perfectly matched system. I built a dorso, but don't even have to use it.

Angela, I've read that if you have flusing... you could try to use a bigger ID standpipe with adapters to what your downspout is. This is supposed to fix it.

IE: If your return is 1"... try getting an adapter to that 1" and building your standpipe from 1.5" pipe.

Also... pvc has different thicknesses. How thick are the walls of your standpipe compared to your return? Its quite possible that your thickness of pipe is actually choaking your downspout.

 

[Angela Short]

Thanks for the brainstorming guys, my dursos are 1.5 and my drain line is 1.5's..... All out of standard sch. 40 PVC from HD. All my Inside diameters should be the same minuse a few glued up conections like the tee and 45 from the farthest one..

 

[gflat65]

Just thinking out loud, but if a 1" hole size gets 1.5" piping in the durso, maybe a 1.5" pipe needs 2" piping in the adjustable part of the durso. I've read that hole size usually doesn't restrict flow (within reason in terms of gravity drain), but maybe the hydraulics are off because you went with a larger drain hole. Maybe send the guy over at the durso website (can't believe I can't remember his name...) and see what he says. he may have a good answer right away.

On the home made durso on the 75 that was dirlled in the back with no room for adjustment (dirlled 6" from the top, like a dummy), the hydraulics were off. Once it hit equilibrium, it was fine. If it lost power, it had a hard time getting the drain and return to balance. I kept drilling larger holes, too, and it didn;t help. Out of frustration, I oput some hair algae over the hole and things started working again. May have just been coincidental, but may be worth a shot. It seems like Rick had some sort of solution to this type of problem (drilling a hole with an air tube fitting that you can adjust with a needle valve or something along those lines), but I never saw it when I was at his house and the 75 is gone, so no need any more. HTH

 

[Angela Short]

I went up to a 1/4" hole in each pipe and it just barely does it now. Just about a inch up and down and you barely hear the gush downward. more of a whistle through the air vent really. I may go on up one more bit size but want a extra set of caps first. thanks for the help.
The durso site says a bulkhead bigger thanb 1" doesn't need oversized pipes...

 

[fishdoc11]

You might try a 3/8" hole.....IME a restricted hole size does cause flushing. FWIW I had to use a 3/8" hole on my 40 breeder to stop flushing with a Mag 7.
I'm really sorry to hear about all your tank losses too
Chris

 

[Angela Short]

I may go bigger than 1/4 when I pick up some new end caps but right now it only fluctuates a inch or so and is pretty quiet. Yea I am bummed about my cool stuff dieing . Live and learn, learning just hurts in this hobby!

 

[phudeb]

Angela, I think if you rasie the durso a bit. Your durso may be too low in your overflow area.

 

[Angela Short]

That may be the case. It is kinds low but not much more than the pic on the durso homepage if any.... I wouldn't fool with the monumental mess it would be to cut them and re-glue them for it. The slight air gush I hear every 30 seconds or so is not bad at all and the water just bounces up and down in them about a inch. As long as it doesn't hurt anything I am leaving well enouph alone for now

 

[rsteagall]

designed correctly... you'd drill a hole through the end cap (capoff) and you can twist it for adjusting the size. Make sense?

Also.. yes What gary said would be the case. Note, this was only a suggestion... on the one I built... I used the same size all the way through.