Solenoid for Return Line?
Brainstorming and planning a sump for my 150g freshwater planted tank rebuild (yet to be started, but the tank's torn down at the moment). I'm worried about flooding the house, mainly because I want to have the return line send water down to the bottom of the tank to help with flow distribution and turnover, but obviously that puts me at risk for a huge issue if the power cuts out and the pump stops. I know there are the customary options of drilling a siphon break hole or a simple one-way vale.
I was looking for something more reliable, like a solenoid valve. Clearly it would need to be open when the power's on and closed when it's off. I believe that's a "normally closed" solenoid valve, if my research is correct. And the continuous duty part is also a difficult thing to find (sort of).
Is there any reason a valve like this is a -bad- idea?
Does anyone know where I can get one for under $300? The one place I was able to get a quote from wanted just over $1000.00 (yes, a thousand) for the valve. WAY too much for this project.
Is there a better alternative?