Loc Line Back Siphon Drill hole?

[Reef_Magik89]

Can someone explain to me the idea of drilling a small hole in the locline pointing down to stop the back siphon?

Some people mention this and also helps to blow any detritus near the bottom of my overflow box?

Any input would be great

 

[mescobar]

you could also consider getting a locline check valve, example from brs

 

[Duckman]

The hole will suck air in after the water level dips below the hole. Once air gets suck into the return line water won't flow by gravity down anymore. It prevents back siphoning of your display tank down to the sump when your return pump stop working. Unless you keep your sump water level low, it's absolute a necessity to prevent overflow of the sump.

 

[Reef_Magik89]

The hole will suck air in after the water level dips below the hole. Once air gets suck into the return line water won't flow by gravity down anymore. It prevents back siphoning of your display tank down to the sump when your return pump stop working. Unless you keep your sump water level low, it's absolute a necessity to prevent overflow of the sump.

So the only way this will work is if the hole is exposed to air?

I can't make the hole near the top of the locline because water will shoot out of it when the return pump is running.

 

[UCT]

Are you talking about a hole in the loc line inside the overflow box or outside the box

 

[Duckman]

the idea is that once the water level falls below the drilled hole no more water willbe sucked back into the sump.

depending on how your return piping is setup u could drill it at the bottom of the pipe so that return pump will spill some water downward

 

[Jimbo327]

Point the hole to the side or down, so it doesn’t shoot up. When level drops, then hole gets exposed and siphon breaks. Hole needs to be a certain size to break siphon.