Can this setup overflow with no power?

[Bengalcats888]

Hi,

I am setting up a tank and filter indoors. Can this setup, when power is off to the pump, cause an overflow from filter in the water back into the tank?

Can water flow back through the pump intake due to gravity?

I just want to make sure I'm doing everything correctly so there are no leaks or overflows, very paranoid. :-|

Thanks

 

[Oughtsix]

Yes, water can flow backwards through aquarium sump pumps.

 

[Bengalcats888]

How would I prevent it from back flow when there is no power to the pump?

 

[Gpdriftwood]

How would I prevent it from back flow when there is no power to the pump?

Just put an inline check valve in the return line. It will allow water to be pumped into the tank, then closes when there is no flow so water cannot flow back into your sump.

 

[esoxlucius]

If that diagram is accurate then i'd be very paranoid too, even with check valves, which have been known to fail if debris gets lodged in them.

I'm struggling to get my head round how your plumbing is set up. Your overflow from your display tank to your sump is fine, gravity fed through 2" pipe. But your return line should also be aiming at the surface, or thereabouts, of your display tank. This helps with surface agitation but more importantly if your pump goes off for whatever reason, you won't get a huge flush of water going from your display tank to your sump, which could result in flooding.

Your return line is going into your display tank near the bottom, so if your pump goes off, and your check valves fail, then you're in big trouble.

I don't have check valves in my systems and if any of my pumps go off all that will trickle down into my sumps is the run off from the display tank until the water level is flush with the drain, a few litres at most, which my sumps can handle very comfortably.

Maybe i'm reading your diagram wrong, someone else will chime in hopefully.

 

[Gpdriftwood]

If that diagram is accurate then i'd be very paranoid too, even with check valves, which have been known to fail if debris gets lodged in them.

I'm struggling to get my head round how your plumbing is set up. Your overflow from your display tank to your sump is fine, gravity fed through 2" pipe. But your return line should also be aiming at the surface, or thereabouts, of your display tank. This helps with surface agitation but more importantly if your pump goes off for whatever reason, you won't get a huge flush of water going from your display tank to your sump, which could result in flooding.

Your return line is going into your display tank near the bottom, so if your pump goes off, and your check valves fail, then you're in big trouble.

I don't have check valves in my systems and if any of my pumps go off all that will trickle down into my sumps is the run off from the display tank until the water level is flush with the drain, a few litres at most, which my sumps can handle very comfortably.

Maybe i'm reading your diagram wrong, someone else will chime in hopefully.

I agree 100%. But to fix your problem you would have to move the return to the tank up to the top, or raise your sump above display tank.

 

[TheWolfman]

If you plump the return pump over the top of your filter, and drill a syphon brake above the water level in it you should be fine.

 

[Rass]

I always drilled a small hole in my return lines inside the tank to break siphon at a predetermined level. Just make sure you have enough extra space in your sump to handle what does drain in a power off scenario.