durso stand pipe

[JoandWilly]

Just finishing set up my new tank and have a durso stand pipe. have drilled a 2mm hole in the top but its sucking in some air and bubbling in the sump, was wondering if there was a way to fix this, whether its making the hole bigger or smaller. Have tryed partly covering the hole but it keeps sucking and bubbling. Will try get a photo up later so you can understand what im on about.

[Drifty]

durso's do bubble in the sump, or at least all of mine have. Only way to get no bubbles is with a full syphon

[suphew]

As above, this is how durso's work. This stops your pipe turning into a full syphon and draining your overflow box, which then breaks the syphon letting your box fill up again, and the cycle repeats. This cycle makes your overflow sound like it is "flushing". It takes some time to adjust the durso air hole to the correct size, but once it is done it shouldn't need adjusting again and your overflow should be very close to silent.

Check out this site for details

http://www.dursostandpipes.com/

The other option is to run a 'full syphon' system to do this you adjust the tap to limit the flow until it is balanced so you aren't sucking air but are still keeping up with the flow into the tank, to use this system you really need another back up overflow pipe because as you can imagine if your flow changes (by something blocking the overflow a little bit) the balance will go out and your tank will flood.

[camnbron]

I had a durso setup with no backup, but now have a full syphon with a durso as a backup.

I only have one hole in the bottom of the wier chamber, so my syphon is a 19mm hose that goes up over the back from within the Weir chamber.

The full syphon has a ball valve on the sump end of the hose to restrict its flow. The idea is to have around 90-95% of the flow going throug the full syphon. It cuts down on noise, and the durso doesn't have to be "tuned" as its just the backup. You know when the syphon has failed - noisy as!

For both overflows I would recommend putting a strainer on them to reduce any chance of them getting blocked

[chimera]

create a bubble trap like this

[JoandWilly]

what parts the bubble trap, any chance you can draw up a diagram on paint or something so i can see how it works

[maxjac]

I have a durso standpipe in my overflow box and I added a piece of tubing down the pipe with the other end left above the overflow - to vent air. This stopped the level of water in the overflow going up and down. Not sure if this is your problem but it worked for me.

[shaneo]

what parts the bubble trap, any chance you can draw up a diagram on paint or something so i can see how it works

The peice of pipe in the middle.

Its just a peice of pvc pipe capped at both ends. Drilled a hole in the top cap and glued in a T fitting with a 90deg, this is incase the bubble trap blocks or cant handle the flow through it. On the bottom of the trap I drilled out dozens of holes for the water to pass through. The overflow is plumbed into the side of the trap (the pipe with the red tap is my overflow plumbing) simple

Any creep you see is what I havn't cleaned off since adding the trap