How to start siphon on overflow box?

[Danny B]

Hey everyone. Ok...after many months of comtemplation/avoidance, I finally gave the Lifereef overflow a shot in my tank (20 gal.). I thought I set up everything properly (5 gal. sump, Rio 2100 return pump) and gunned it. The return flow was fine but I couldn't get the siphon to start. I thought it would start by itself for some reason. After a minor flood, I tried it again this time trying to start the siphon in the J-tube using an extra piece of tubing to start it then quickly dropping the J-tube in the box. We kept trying to no avail. I'm about ready to scrap the idea and just go with an H.O.B. skimmer. What am I doing wrong?

 

[914]

use a piece of airline tubing... sometimes and old piece that's stiff from the pump output is best, but certainly not the floppy silicone stuff.

anyhow, put the U tube in the water so that *both* ends are underwater. obviously, you must fill the back chamber of the overflow box for that.

thread the airline up the tube until the tip of it is at the peak, or even a little towards the outside of the tank (more on that in a sec)

(you can thread the airline into the U tube before you put it into the overflows, but you must end up with both end of the U submerged, and the airline in the U at it's peak)


use your mouth to suck all of the air out of the U tube. as you suck, the water level will rise equally on both sides of the tube, until they meet.

then, water will start to flow over the U into the overflow.... the trick is to keep sucking air (not water!) until the bubble is as small as possible.. as long as your overflow is sized correctly, the small leftover bubble will be swept out of the tube by the flow.


puttin the airline a little towards the 'back' of the U tube makes getting most of the air a little easier, since as soon as the flow starts (when the water columns touch) the remaining air will be pushed in the direction of the flow.

did that make sense?

once all that's done, *carefully* pull the airline out of the U tube, without ever letting the tips of the U break the water surface.


if you're squeamish about sucking it by mouth, you can attache the airline tubing to a powerhead, use the little 'bubbler' port, often found on the output nozzle of powerheads.


good luck!

 

[Bodine]

Place a section of airline tubing in the J-Tube and with the end submerged, evacute the air from the J-tube by sucking. The siphon should start. Remove the airline tubing

 

[Danny B]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by 914:
<strong>use a piece of airline tubing... sometimes and old piece that's stiff from the pump output is best, but certainly not the floppy silicone stuff.

anyhow, put the U tube in the water so that *both* ends are underwater. obviously, you must fill the back chamber of the overflow box for that.

thread the airline up the tube until the tip of it is at the peak, or even a little towards the outside of the tank (more on that in a sec)

(you can thread the airline into the U tube before you put it into the overflows, but you must end up with both end of the U submerged, and the airline in the U at it's peak)


use your mouth to suck all of the air out of the U tube. as you suck, the water level will rise equally on both sides of the tube, until they meet.

then, water will start to flow over the U into the overflow.... the trick is to keep sucking air (not water!) until the bubble is as small as possible.. as long as your overflow is sized correctly, the small leftover bubble will be swept out of the tube by the flow.


puttin the airline a little towards the 'back' of the U tube makes getting most of the air a little easier, since as soon as the flow starts (when the water columns touch) the remaining air will be pushed in the direction of the flow.

did that make sense?

once all that's done, *carefully* pull the airline out of the U tube, without ever letting the tips of the U break the water surface.


if you're squeamish about sucking it by mouth, you can attache the airline tubing to a powerhead, use the little 'bubbler' port, often found on the output nozzle of powerheads.


good luck!</strong><hr></blockquote>

Thanks for your help 914 and Bodine. Once the siphon starts I should then turn on the pump, correct? Thanks again.

 

[Anonymous]

Wow, very good description, 914.

I do my water changes from my sump. As I fill the sump back up, I turn on the pump and watch for it to start filling the overflow (there's already water in the back box) when it gets to the bottom of the J-tube, I use the hose to get the air out. Just make sure your hose is nice and long - tank water can be raunchy in your mouth. I'm sure most of use have been there though

 

[Danny B]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by tangirl:
<strong>Wow, very good description, 914.

I do my water changes from my sump. As I fill the sump back up, I turn on the pump and watch for it to start filling the overflow (there's already water in the back box) when it gets to the bottom of the J-tube, I use the hose to get the air out. Just make sure your hose is nice and long - tank water can be raunchy in your mouth. I'm sure most of use have been there though

</strong><hr></blockquote>

tangirl,

so when you do water changes you turn the whole system off? i'm sure this will get a lot easier once i get the hang of it. i'm just a little frustrated right now. btw, do you know of a good method of attaching the outflow hose to my sump (rubbermaid tub) without having to drill a hole in the side?

thanks,

Dan