Filling a sump

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Alvanck

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Hi All,

Recently got a new set with a sump. Not going to lie I’m nervous about leaving it running for the first few days when I’m at work. What’s the best way to fill a sump and/or tank to prevent overflow if there where to be a power outage or pump failure?
 
Your sump will only take on as much water as your display allows. How big is your display, and sump and how much water are you running in the sump normally? 1/2, 2/3, 3/4 full?

How is your display set up? Are your returns and overflow both up high on the displays back wall? Most are. So when the power goes out and return pumps stop, only the top inch or so will back flow into your sump. The water will stop back flowing into the sump as soon as the water level is below the lowest opening in your display. So as long as you don’t have a bottom drain or closed loops with returns and drains low in the display, only a small portion of your display should drain back into your sump. So if you are not running a severely undersized sump,or have your sump way overfilled, you should be fine.

You can always add back flow preventers on your return lines to help.

You can always test it by turning all your pumps off and see. I would do that anyways just to be sure. If you notice the water getting to close to the top of the sump then turn your pumps back on.
 
Is a 90 gallon,

Returns and overflows in the corner. Sump is an RS-100.


20260726_090703_215CDF53-C56F-4A8A-8726-2AA664A675C5.png
 
Is a 90 gallon,

Returns and overflows in the corner. Sump is an RS-100.


20260726_090703_215CDF53-C56F-4A8A-8726-2AA664A675C5.png
What are you using for a return? If it's an over the back, J hook type, you can drill a small hole in it right at the level of the bottom of the teeth in the return. Fill the tank so the water is to the teeth. Fill the sump to the fill line, if there is one, or till the water is just below the filter sock holder.

When you turn off the return pump, the water will backflow but the siphon will break at the hole in the return hook and the sump won't overflow. Test and adjust as needed. No worries then 😎
 

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