Silly Siphon Question

[parker313]

OK, I am trying to get my tank set up. The tank was not pre-drilled so to get the water to the sump, there's a u-shaped tube from the tank to the "return box", if that's what it's called. My friend who I got the tank from showed me something with a piece of airline tubing to get the flow started but I must have missed the specifics. I do have the return pipes and pump ready to go so I can start those if I need...

How do I get the suction started to get the water from the tank to the sump? I'll go get a picture of the setup.

Thanks,
Kristin

 

[parker313]

OK, pictures:

 

[parker313]

Haha, nevermind. I am watching my friend's dog for the next 10 days and her husband, who actually ran the tank, brought the dog by and showed me how to get the system going

 

[bitteraspects]

Make sure both sides of the "U" tube are under water.
Get a length of airline tubing and stick it in the "U" tube from the tank side.
Push the airline into the "U" tube so that it is in the middle of the tube at the highest point of the arc.
Suck on the airline tubing pulling out the air from the middle of the "U" tube until it it filled with water. (you may have to add more water to the back of the overflow box while you do this)

 

[parker313]

That's exactly what he did - it just seems so counter-intuitive b/c you want the water to flow from the tank to the overflow, yet you're sucking from the overflow towards the tank!

 

[bitteraspects]

All you're doing is pulling the air out.
Because the "u" tube is longer in the back and the overflow box is also lower in the back, gravity will still pull the water from the tank out the back. the "U" tune is just easIer to access from the front.

 

[ben1987]

What happens when you get a power cut if you have to manually start the siphon?

the return pump stops working so the siphon stops, power comes back on - no siphon = wet floor.

 

[bitteraspects]

When you turn the pump off, the water level in the tank drops below the inner skimmer box. However, the "U" tube maintains its prime (stays full of water). when the pump is turned back on and the water level rises back above the inner skimmer box, the overflow will continue operating in its regular fashion.
Generally, after its initial prime you should not have to do it again unless you physically remove the "U" tube, or if cavitatiin occurs. There are measures you can take to prevent the later.

 

[parker313]

What happens when you get a power cut if you have to manually start the siphon?

the return pump stops working so the siphon stops, power comes back on - no siphon = wet floor.

Also, the pipes that pump the water back up to the tank will act as a siphon if the power is cut, but as soon as the water level drops down so the ends of the pipes are exposed, there won't be any suction anymore - so, the base level for the amount of water in the sump is to cover the pump, plus leaving enough room for the return of water from the piping and any extra that will get siphoned back up.

I have a 20g quarantine tank and a 10g sump and am considering switching them.

 

[bitteraspects]

I too prefer a larger sump. It leaves you room for more options down the line.