How many gallons of water should be cycled through the sump?

[Leafy]

The sump tank is a 15gal. that rises about 30" to a 33gal. I have this overflow box .

 

I wondering how powerful the sump pump (gph) should be for this setup.

 

Thanks!

[MrConclusion]

That depends a little (sarcasm) on what kind of "sump" you have. If it's a simple (sarcasm again) refugium, then tremendous flow isn't necessary. If you have lots of biofilter ar chemical media, then you might want a bit more.

 

Fortunately, with a 30 gallon tank you need way less flow than your overflow is capable of maintaining. I would suggest something in the 100-300 GPH range. That's actual GPH, not the rated-max flow of the pump, which is uaually at 0-foot lift and with everything new and squeaky-clean.

 

If I were you I would get on e of the mid-sized Eheim pumps. They're silent, versatile (easy convert from submersible to external) extremely reliable, and also extremely energy efficient, so they don't dump a lot of heat into the system even if used submersibly.