HOB Overflow Boxes?

[BlazinNano]

What does everyone think of these. How dangerous are these when it comes to loosing siphon if power is lost. I have one that I have not setup yet. The way the plumping is set up o it the box will always have water in it because the down tube sticks up in to the box about 4 inches. Therefor the the J-Tube will always be sitting in water at least the side that is in the back of the box.

 

[Ladipyg]

I had a problem of the tube sometimes being moved and my not noticing it and therefore I lost siphon...a mess when the power kicks back on. As a safety measure I took a clear soda bottle and cut the top off so that it extended up the tube about 6 inches or so and notched a few teeth into the top. Never had a problem after that and the soda bottle did not interfere with the flow coming into the box. The only other thing is be sure to have a pin hole to break the siphon on your return lines and be sure they stay clear and do not get clogged with salt or you may overflow your sump.

 

[mevstheworld]

This is what I use. http://us.st12.yimg.com/us.st.yimg.com/I/yhst-75495311174416_2047_3876905 the divider in the middle is what keeps the siphon. Once the water drops below the divider, drainage stops therefore keeping the u-tube filled with water(overflowbox in tank = box outside tank) the water has equal pressure on both sides so no water movement. Everytime i do a water change I just shut down all pumps, my sump fills till the back siphon is broke and my HOB overflow box stays the same. Then I just start the pumps back up and the water fills the box and water then starts flowing again. Hope this helps.

 

[Ladipyg]

mevstheworld, that's a good one...mine wasn't like that when I got it and was new to HOB overflows...using the bottle just took it's place for me. Needless to say, my new tank has built in overflows this time.