Siphon in, siphon out - risks?

[SoloSK71]

I am planning a hang on tank refugium to grow pods and chaeto and was wondering if there is any risk to a dual siphon system, one feeding from an overflow box in the tank into the refugium and the other feeding out of te refugium down into the sump?

Charles

[mark]

flood if you loose siphon out and just guessing but would imagine difficult to match each over time

[SoloSK71]

The refugium will have the same water level as the DT

Charles

[1eyedjyde]

If the levels are the same it won't flow. Doesn't there need to be a difference in head to syphon. You could use a syphon from the tank to the fugie and then have a stand pipe drain down to your sump.

[AquaPin]

Do not think it will work, you are going to need pumps in and out or an overhang for the return.

*Syphons work on differences of pressure created by differences in height. The pressure difference is minuscule but it is enough to get the flow started, and keep it going. Once the heights are the same, there is no pressure difference, hence no flow.* - Yahoo

[gregzz4]

The siphon will work if I understand your plan
The line to the sump will be enough
But, you need to be able to stop it when the return pump is off, so I'd suggest you don't do it unless you look into setting it up the same as a hang-on back overflow box with an in DT box, u-tube from box to fuge, and something like a Tom's aqualifter to restart the siphon after a pump restart
I'd also use a valve on the drain line to the sump so you can dial in the flow rate through the fuge

Have a look into how hang on overflow boxes work before you buy any parts :wink: