closed loop

[davesolo29]

i have a question... will be doing my research after supper, but figured i would ask here first to get the ball rolling.

Im in the process of plumbing my display tank, and rather than cover the previously drilled bottom holes from the cornerflo system, im considering doing a closed loop. 
My question is this,  how do you create a syphon break in a closed loop.  I mean, the bottom returns are obviously well below the the water surface.  I really dont want my entire tank to drain in the event of a power outage.
Im sure its simple and once i google it, i will find lots of answers.

 

[Neopimp]

There isn't. Closed loop is closed. Just a suction and an output from a pump.  No sump

 

[pulpfiction1]

a closed loop is that,a closed loop,nothing to loose in a power outage,water comes to your pump which in turn pumps it directly back into your tank,maybe a couple of shut offs in case you need to replace your pump,the idea is to create water movement ,nothing more,water out,water in,in a closed loop

 

[davesolo29]

ah... so i would need a second pump running dedicated just for that.

 

[phi delt reefer]

Yes a closed loop would run on its pump. The inlet and outlet and plumbed to the display.