Adding additional tank to system- plumbing help

[GOSKN5]

Forgive my drawing (I can’t)- but I am thinking about adding a drilled cube tank that I have into my current system. Like to make it a display refugium maybe.

Would this plumbing work? Any concerns with this plan? How about when the pumps are off with back flow into the sump/extra tank? I know I might need a couple valves to control the flow and a strong enough return pump.

Thanks for your help!

 

[nuxx Verified Sponsor]

What about putting it just inline with the sump?

 

[GOSKN5]

What about putting it just inline with the sump?

I would prefer not to drill the sump and also the drain from the display is on the other side of the sump and hooked to a roller mat etc- I don’t want to mess with the drain portion.

 

[TokenReefer]

I like this design (I'm doing something very similiar...hung a 20 gallon onto my sump) because it has one pump and lets gravity do the rest. Feels like this is the least complicated way imo. All you have to account for is the amount of water that will fall into the add and how much from the add will fall into sump when power goes out, simple math...