I program my gyre with my apex to ramp down at night and then work at a reduced flow. No science behind this that I know of, but changing flow patterns seem to keep SPS happy.

I drop mine down to 20% at night

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You can turn down (as many members on here do), just don't turn off. Its the current and wave action at the surface that aerate your water. I have a high bioload but lots of hiding places and areas of lower flow so I leave my wavemakers on all the time. The fish don't seem to mind and neither do the corals.

I use the jebao apex module to program my powerheads and have them set at minimum for the night, before that I had a led light strip in my cabinet on a timer and the pumps would be set to night mode.
I leave my return pump at the same lvl so the circulation stays the same, just the powerheads are reduced.

I use night mode on my Jebao RW-15, my electronics are in a closed cabinet so I have a small LED light on a timer, works well my return flow stays constant.

Yes they have a programmable night mode built into the factory controller.
4 speed settings to choose from, and 6, 8, 10, 12 or 14 hours.

Do they have a photocell?

No photocell
Program your speed and duration, then press some buttons at your desired start time.

A controller will give you many more options then the pumps built in mode, but it all costs $$

There are no options a controller can provide that my VorTechs don't already include. Sometimes it's worthwhile to spend the extra $$s on a well designed water moving device. And yes, I use the night mode, not because of any possible relationship to what happens in the ocean, but more because it saves power, wear/tear on the pumps & things are a tad more quiet in the dining room over night..... but no, I don't sleep in the dining room.... usually.