I have my mp10 on Reef crest 24-7 it ramps up a down the whole time. I think the ocean has flow cycles as well but never has no flow so I always leave it on.
Two mp 40's controlled by apex at night it goes into night mode and run at about 50% in sync mode durning the day the run through different settings at max 90%. I try to give the tank a more relax flow at night so that my fishes don't get blasted with flow when they are sleeping.
I guess that is the more relevant question. How much does the ocean change at night?
I have two WP25s. I use the else setting and have them restricted with variable power supplies. They are supposed to cut back to 50% in night mode but the sensors don't work very well so I took them out. I was thinking about turning them off at night. I would still have flow from the return pump.