Need Help with Hang-on-Refugium

[ColaAddict]

I was thinking of using a CPR medium HOB refugium, I use one now in my bigger tank, hanging on the sump, and whenever I turn the refugium pump off, the water from the refugium siphons back into the sump. How do you guys keep the HOB refugium from back siphoning the water back to back of the tank, causing a flood, when the pump is turned off (say during a power loss). I could'nt find any check valve for that small of a tubing/pump, if you use a check valve, where did you get it?

[NT Nano]

Drill a small hole just below the water line... When the water level drops below the hole, air will enter and break the siphon...had to do the same on my CPR HOB fuge

[ColaAddict]

Drill a hole on the PVC inside the refugium, right?

[aquaenthusiast]

Yes drill a hole right where you want the water level to be inside the refugium, so when it siphons, it will draw water and then when it drops down to the hole it will draw air and break the siphon.

[ColaAddict]

great thanks

[sweetyness]

Thanks! You helped me as well!! Worked like a charm.