Not sure if I'm phrasing it properly. I am under the impression that when using a HOB
overflow box, the siphon is broken when power cuts off and water back flows into the sump via the return outlet.
The actual question is:
When the power comes back on and the return pump starts filling the main tank again, will water OVER flow from the main tank since the initial siphon in the HOB
overflow box is lost?
I'm considering getting the CPR overflow box, but can't get my logic working. This will only work if the siphon is never broken when power is lost. That way, when the return pump starts filling the tank, the gradient is restored and no overflow occurs.
Maybe I should just invest in a tank with a drilled overflow...grr...