HortiMaX Go! User Manual page 15

If you tap the start or end time, a screen will open listing the start times of the four
periods:
By tapping the different periods, you can choose whether a period should start based
on clock time or relative to sunrise or sunset.
Start time based on clock time
Start time before sunrise (e.g. 1 hour before sunrise)
Start time after sunrise (e.g. 1 hour after sunrise)
Start time before sunset
HortiMaX-Go!
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