I have two, and I have them ramp up to a higher percentage when the lights are on. The theory being that more flow during photosynthesis is beneficial.
One of the pumps pulses for about 3-4 hours (the other on random), then about a one hour period of both on random, then the other pulses for 3-4 hours with the first one on random. I then have them both spin down at night to about 10-15% steady overnight.
For about a year I just left both on random and that was just fine as far as turbulence. I only went to the pulse function because I have anemones and the motion with the pulse is really cool to watch.
If you do go pulse, I’d like to make a suggestion... adjust the settings such that the pump never spins down to “off” between pulses. I played with the sliders until I got it to the point where just before the fan would stop, the next pulse would begin. Reason being that I’ve read about people losing fish to these pumps, and while I have no evidence to support this, my theory is to avoid those moments with complete lack of intake flow. The surge following those “off” moments seems dangerous to me. I made this change around 6 months ago and my fish still go no where near these pumps.