At my Wit's end with Durso Standpipes

[Aquariust]

OK everyone, I've spent 3 days straight messing with the standpipes, and I can't get them to work properly.

My tank is a 120 with an ampmaster 2100. All of the plumbing is 1 1/2 PVC. The sump has baffles, etc.

The tank is working perfectly, except for the overflow chambers. I've read dozens of posts, and can't find a straight answer.

This is what happens: I start with no holes on the cap of the durso. Water gets sucked down to the sump really fast. I start drilling 1 hole at a time in each durso. If it's not enough, I make the hole bigger. If that's not enough I drill a second small hole, then make it bigger, etc... Usually what happens is one of the overflow chambers will be filled to the top, and the other goes up and down making a flushing sound (gurgling - sucking air). What's weird is that it's almost like the durso knows it has to put more water in the sump because the pump will start pulling more water than the durso will give, and right when it get's to the pump's intake, the overflow will blurb, fall, make the gurgle sound, and fill the sump back up. If I cover one of the holes on the top of the cap with my finger, the fuller overflow will start sucking air too.

I've tried reducing backpressure in the drain lines by having the lines only submerged a half inch. I've tried turning down the pump, I've tried turning down the pump and overlfows with ballvalves. I made custom 2 inch durso's instead of the original 1 1/2" ones. I've made nine million holes on the caps, covered them up, and re drilled some.

The only thing I can now think of is to put the drain lines into a Y so they aren't seperate entering the sump. Perhaps my durso's are too high?

I'm waitng for some silicone to cure so any ideas or suggestions over the next couple days would be very helpful.

Thanks,

-John

[Jimbo]

DO NOT submerge the lines in the sump. Pull them out of the water - that may solve your issues.

Jim

[Aquariust]

I tried to keep the pipes un submerged. It was very loud. I still had the same chamber problems. I know have them submerged and it's working OK.

My biggest problem now is that I think I get less flow on the left than the right. I re- designed the plumbing with all flex pvc and no fittings. The flow is good but still not the best.

The right overflow has a quick shoot down the durso right into the sump. The left has to go 4 foot to the other side of the stand. It still gets good flow but not as much as the right.

What happens is the right overflow will stay right where I want it, an inch or so below the surface. The left will stay even with the surface, like it's not pulling enough water. I've tried turning down the flow on the ballvalves to try and equal it out, but then I have to turn the pump down to match, and I get low flow from the returns.

Any ideas?

I'll ry and post some pics today or tom.

[NewMariner]

If your still getting a gurgling noise then you still arent getting enough air in the top of the cap.

I have a 2in drain on my 180g. It was gurgling bad....and surge....The surges were so powerful it overflowed my sump. So I just kept drilling holes into the cap. I have about 3 holes the size of a straw in the top of my cap....My overflow is now silent and doesnt surge and gurgle anymore....

You might try to stick an airline hose down one of the holes and into the pipe......Ive heard that works......

[mbort]

I am fairly certain that the problem is due to the long flow path on one side as opposed to the other .. probably difference in flow resistance (from elbows, etc.) .. What may work is running both of the overflow lines into a T that then feeds a large single line into the sump .. if the line is submerged, it will help assure equal back pressure coming from both sides into the T, and may alleviate your problem.

Maybe also try a Stockman mod .. I have used this with better success than my Durso. Works on similar principles though.

Good luck.

[NeuroLarry]

You didn't say if your tank was an AGA but I doubt it if you have room for 1 1/2 " pipe in the overflows. I built mine according to the plans on Rich Durso's website and they worked well with only a little tinkering with the vent size. I have seen reccomendations for putting airline into the vent hole and controlling the airflwo with a small valve.

[jayjellyfish1]

do you have ball valves on the durso's . i do and it helps regulate the balance of the 2 over flows. if you need a pic let me know.jjf

[Aquariust]

Originally posted by jayjellyfish1
do you have ball valves on the durso's . i do and it helps regulate the balance of the 2 over flows. if you need a pic let me know.jjf

Yes I do have ball valves on all the lines.

Larry I am using an air valve, but I might give the airline a go. My tank is an AGA, but not a RR. I drilled the tank myself, and made my own overflow chambers. They can fit the 1 1/2" return lines and 2" durso's in each chamber.

mbort, that's what I was thinking too. I think I might give it a try. I'll get a reducer from 1 1/2" to 2", and then try and get them into into a 2" Y. I wonder if it would add noise to the design? I finally have it pretty quiet.

[MrSandman]

Maybe you just need to fine tune your durso to find that "sweet spot". Instead of hooking up ball valves, or air lines to your durso, or making swiss cheese out of your durso caps, just do this:



That cap is the top of my Durso. On the cap is a small vent hole that is drilled clear through. To adjust the amount of air, i just turn that cap a tad to either make the hole larger or smaller. I was able to fine tune it in a heartbeat and haven't had the need to mess with it since.

[Rockfish]

I just did mine this weekend. I have two overflows, one on each end. The drains are 1-1/2". I used to use two 1 1/2" gate valves to regulate the height of water in the overflows and minimize water rushing noise. What this got me after 10 months like this was a less than optimum sump turnover and a clog in the valve due to it being closed up too much. I then had a overflow. You'll have to read my Durso Believer post from today to see the entire story. Anyway I used a 1 1/2 to 1 1/4 thd converter to screw into the bulkhead drain, then went with 1 1/4 pipe up to a 1 1/4 tee. Downturned a 1 1/4 90 and off the top of the tee went with a 1 1/4 to 1/2 thd fitting. Of which I screwed a 1/2 x 1"L nipple into it. I then threaded a Sprinkler Bubbler on top. If you have ever seen one of these in action, you turn it to let more or less water gush out. Same theory turn to let more or less air in when using on the durso. Works like a charm and no damn holes to drill. Now I leave the gate valves full open and water goes into the sump like the speed of light and no more water rush noise. I do not have to worry about a clog anymore either. Most importantly the tank is twice as quiet, I have a constant height of water always in the overflow, I do not have to tinker with the valve anymore to adjust height, and it is unaffected by evaporation in the sump, and the wife is happy. I have a higher turnover and I am producing more skim out of my skimmer due to more circulation turnover into the sump. I can't beleive how I did not attemp doing this 10 months ago. Hope this helps.