I just swapped out a DC pump on a 24x24x24 cube this evening and learned a few things about High flow.
Obviously, flow keeps the turnover rate good and fish healthy.
To not push substrate, I open up the small nozzle-like output to be a bit more volume friendly (oversized output).
Use a small powerhead inside the tank if needed (no need currently).
For flow, up until tonight, I ran an Ecotech Vectra M1 model on Setting 10 of 12 and had great success on the 60gal cube with a 20gal sump.
It was running hot on the pumps transformer using 1" I.D tube to the display.
The new Elos pump runs at 36%, stating 38 watts used.
It is a 2905gph pump on High.
I cant run the pump any higher. The pipe that lets the water drain (3/4" I.D pipe) is almost maxed (no problem).
If the pipe clogs with a snail, the emergency takes over. Look in your bathroom sink. The sink has an emergency too. Little holes near the side closer to the front.
Just about all pumps vibrate and make noise, so turning it down takes most of the noise out of the room.
Running a pump at 1/3 speed keeps it very quiet, but still very fast in cycles per hour.
It is about the same level as the kessil A160WE above the tank now.
-Just a little spinning noise when you put your ear down by the sump.
No heat issues with the Elos pump and the water line is a millimeter or so higher, so I'd say the turnover is higher than before while still saving total watts.
I have to change the foam filer blocks down in the sump every 3 months, just because I like to.
Go High flow, low watts. The turnover rate is awesome.
-Initial equipment cost is always a bummer.